another turbo question

[SVXMAN2001]

How much hp can a single turbo add to the svx? doing a turbo would require the fuel injectors to be upgraded right? Is there any chance for a twin turbo setup? would the custom front end free up more room for this to be even fathomable? also are there any modifications that can be done to t he engine itself? thanks
chris 92 claret svx

[cdigerlando]

I installed a turbo an oil cooler, and exhaust for about 4,800. There was no significant increase in performance. I am now adding a Tec II $(2000) and nismo fuel injectors (1100). I will also have to tune the car, which may cost up to $500 to do it on a dyno. I should also replace the torque converter and have the valve body recalibrated for about $1200.

Close to $10,000. Still interested? My recommendation....buy a WRX. I also own one, and I could CHEAPLY produce much better performance in a much better all around performance package. Unless you have lots of money and a THING for the SVX, I wouldn't do it. If I had known about the WRX before buying the turbo, I would have never started this project.

I hope this post has not been too depressing.

[KEVINL]

Lets clear some things up here I have just the turbo kit and if I wanted to thats all I need. But I want more power. so the resistor mod and the turbo is all you need but what you want is something completly different. BTW The WRX doesn't appeal to everybody yes the WRX comes factory with a turbo but it doesn't have the looks, luxury, refinement and low down power of the SVX

I don't know the exact hp But with 5 PSI 100HP sounds fair
no twin turbo available or needed most of the Supras and RX7's that have huge power have been converted to a single large turbo

[cdigerlando]

Kevin, I have run this car at the track. The best time it ran with the turbo, resistor mod, intake and exhaust mods is 16 flat. That is not with the rising rate fuel pressure regulator that some of you use. That is no better than what a lot of SVXers are seeing with a level 10 tranny upgrade, and worse than people that have installed chips with more agressive timing NA. 100 HP is NOT accurate. No dyno of this system has been done, and I have not seen any better times than a 15.3 1/4 mile posted for the turbo.

Mind you I am not dissapointed in what I got. The kit Robert put together was excellently crafted to fit. I fully expected to have to change out fuel injectors and do fuel management. It is a necessity in my opinion. I'm sure that if you and Robert put your heads together you could come up with a cheaper solution, however that has not been made available, and I cannot in good conscience say that this kit produces significant gains in itself.

I will keep you guys posted on my mods and share any programming I do with you. I seriously hope that I can break the 13 sec 1/4 mile with all of the damn money I am dumping into this car. If I can't, I will be yanking the engine and replacing pistons next.

As for the WRX. It is an awesome car, and a hands down better performer than the SVX any day. I do think that the SVX has potential, just like some of the bat out of hell turboed RSs that are running around. The power just has not been realized yet. Unfortunately many SVX owners are not expressing the kind of interest in power, necessary to make these modifications more commercially available.

I don't think that anyone should get into this kit without realizing that a lot more needs to be done to make the car really go. The only mods which have really panned out so far is the nitrous.

[KEVINL]

how did u only pull a 16. I may run my car as soon as I get a replacement tranny for it. I am tired of these terrible turbo SVX times

Btw if I pull another dissapointing time I am going to sell my SVX

[1994SubaruSVX]

are you that frustrated with the performance of the car? i just cant imagine selling the SVX......you must really be interested in hp. i guess i can understand that. it is going to take some serious money to tap the potential of the SVX. good luck kevin...:)

[cdigerlando]

I spoke with Robert about fuel and engine management. He is really good with that stuff. He even recommended a system that he could put together from a junk yard ECU and '95,'96 300 ZX turbo injectors which you could get from someone selling theirs who have upgraded to nismos.

You could do that, or spend the money for a new Tech II and injectors. This is just lots of $$$. I would wait for me to finish before you do this. That way if I blow up my engine you will have not lost any money too. I will also share my programming with you. Robert could help you fine tune.

As for the need for power.

Remember what Tony Montana said
"First you get the money, then you get the power, then you get the Women."

This is what I say

"First you get the woman, then you spend the money on the power, and the woman leaves you because you spent all of the money."

I feel that is more accurate. But if you can talk her into a single car purchase with fewer mods, it might actually be better on your relationship. Hence the WRX recommendation. :cool:

[KEVINL]

Well its like this I have put a lot of money in my car and I dont expect it to pull 12's but 16's and 15.3. That doesnt cut it I ran 16.2 In my 1988 Subaru that only had the boost raised. and I didnt have a lot of money into it MY SVX I probably have over 10K invested in it drives very well and looks awesome. But those horrible times makes me feel like Im throwing money in the trash. Although I am the only SVX-t turbo owner who has had no problems with running lean loosing boost or running to much boost the turbo kit on my car is flawless but this doesn't insure I will run respectable times. If i cant run a respectable time in my car I am going to stop. come on supposedly SVX should run 15.3 stock what happens 18's stock that is downright horrible. I want to go fast and 15.3 with a tubo makes me feel I should run down the track maybe I could get a better time.

In conclusion I love my SVX but I want to go fast if I cant have both maybe I should look else where than the SVX for speed

[SVXtypeR]

...I'm not getting this whole "no power" thing, maybe you could help me out. What altitude are you at? How many PSI are you running? What trim is your compressor/turbine? Any aux fuel or ignition mods? Any charge air cooling?

The reason for the flurry of questions is that I find all these turbod' SVX times incredibly low. The SVX has the LARGEST displacement motor of ALL the Japanese supercars (even the mighty NSX is only a 3.2 after all these years)!! I'm totally flabbergasted that all these breathed-on H-6's are only putting enough power down for 16's, 15's and (on rare occasions) 14's. IMHO this car should be looking at high 13's MINIMUM for a decent turbo setup.

I've seen pictures on SUBARU-SVX.COM of one guy's turbo conversion, and frankly, the kit looked really poorly designed (most notably the exhaust). I'm not sure what brands are running around, but it sounds to me like there's a missing link at minium, but not limited to, the ECU. I'd like to start a poll on SVX forced induction conversion performance, and, if you don't mind, I'd like to start with you.

TIA

[svxistentialist]

Originally posted by KEVINL
Well its like this I have put a lot of money in my car and I dont expect it to pull 12's but 16's and 15.3. That doesnt cut it I ran 16.2 In my 1988 Subaru that only had the boost raised. and I didnt have a lot of money into it MY SVX I probably have over 10K invested in it drives very well and looks awesome. But those horrible times makes me feel like Im throwing money in the trash. Although I am the only SVX-t turbo owner who has had no problems with running lean loosing boost or running to much boost the turbo kit on my car is flawless but this doesn't insure I will run respectable times. If i cant run a respectable time in my car I am going to stop. come on supposedly SVX should run 15.3 stock what happens 18's stock that is downright horrible. I want to go fast and 15.3 with a tubo makes me feel I should run down the track maybe I could get a better time.

In conclusion I love my SVX but I want to go fast if I cant have both maybe I should look else where than the SVX for speed

I am no expert in drag racing, it is not the done thing over here. However, I can see no point in trying to turn an SVX into a fast strip car, it goes against everything the car is about. Two things are against you here, the car is too heavy, and it is carrying too much weight.:D

230 hp is a lot in a small car like an Impreza, it can not haul a$$ in something the size of an SVX. Remember Scottie? Ye can nae change the laws of physics, Jim?

Having said that, here is my 12s formula:

The box must go!! The autobox is only just able to handle the torque it gets from standard engine tune, it will be pummelled by upgrade power. Put in a six speed manual box from a late model Sti, it would need a plate made, but would be 4wd and would fit, and is built to take the 400+ bhp these things handle. Plus the six speeds will give you low enough ratios to launch all the weight. Should cost 4-5 K

The engine: Fit a supercharger for linear power. You might have to live without AC. Or, maybe better, put in the twin sequential turbo set-up from the Mazda RX 7, and a couple of other Japanese rockets. The advantage, you are running on low boost all the time before the main turbo spools up and blows in, so you would not get the sort of lag a big long-ish stroke engine is going to show when the compression ratio is dropped for the turbo. You would need a serious mechanic though.

Joe:)

[svxistentialist]

Which reminds me, a far cheaper option. Buy the rebuilt Legacy box from Randy. Fit it and also fit the rear Legacy diff so you can run it 4wd and don't have to be pulling fuses and stuff. This will give you a lower final drive in all the gears, you can make all that torque work for you.

The piece de resistance, run with a set of race wheels, 15" set running 205 rubber should be just right. These will have enough grip to get away, but will have a nice bit of a lower rolling radius to drop your final drive another little bit. Use high traction race rubber such as Yokahama, they won't last long, but you won't want them to.

This should be a cheap way to drop a second or two, especially if you are already running a turbo.

Joe

[eddycat2000]

Originally posted by KEVINL


In conclusion I love my SVX but I want to go fast if I cant have both maybe I should look else where than the SVX for speed

Yes, you should look elsewhere. The SVX wasn't built as a dragstrip type of car. It was built to be a touring affordable luxury (kinda, sorta) type of car.

If you want fast drag times there are many cars that are cheaper to maintain and easier to work on than the SVX! The only person I know of that has respectable times in his SVX would be peepee, his SVX is rated at 983 HP <shnicker>. :D :D :D

[svxistentialist]

Originally posted by eddycat2000


Yes, you should look elsewhere. The SVX wasn't built as a dragstrip type of car. It was built to be a touring affordable luxury (kinda, sorta) type of car.

If you want fast drag times there are many cars that are cheaper to maintain and easier to work on than the SVX! The only person I know of that has respectable times in his SVX would be peepee, his SVX is rated at 983 HP <shnicker>. :D :D :D

Now I know why you are schnickering and :)ing broadly, but he who laughs last is just slow to get the joke. Don't forget, before F1 banned turbos, they were getting stupid horsepower figures from 1.5 litre engines.

Pepe is probably getting that from one bank of cylinders! Also Eddy, I am watching the powerseekers with interest. The H6 is so understressed compared to say a BMW M3 or M5, that it must be possible to extract a few [50, 60??] horsepower, without turning the car into a ricer or noisebox police magnet.

This is all I want, absolute silence and absolute power. Is it so much to ask??

Joe:D

[svxistentialist]

on drag racing. I have an article from a couple of years ago, with some tuned American cars which really opened my eyes. One was a Viper with enough horsepower to burn out the tyres at any speed. But the cream was a black Corvette[last model] tuned by a guy called Lingenfelter I think. It also sensibly had uprated suspension and brakes, and ran on huge Fikse chrome wheels which were a bit OTT, but worked. This car could go 0-100-0 in about 11 or 12 seconds. Now that is serious $hit!!

If you fellows can get this sort of tuning and power for small money, I am surprised you would be bothered to try and turn the SVX into a racer when it is an excellent GT car. But if you get an extra 20% without major surgery, I will be watching.

Joe:cool:

[cdigerlando]

I did and still do like the SVX and think it does have potential to be a fast cars. Its just more expensive than doing this with a WRX which is set up to run induction. You are right in saying that this is an ECU related problem. Very sophisticated tuning is required to run forced induction on an engine having 10:1 compression.

As for the weight....I think that everyone is right in that most cars are lighter, but not all. Look at the 911 turbo. It is 3500 lbs too.
It is also about 425 HP! You are also right in that 400+ would be necessary to meet these goals. That has been my goal all along.

My point in my previous post is that Engine management is necessary to make ANY aftermarket turbo kit really work well. This is an added cost that is an essential part of any well designed kit.

As for the turbo it is a T04 garrett turbine with a T03 compressor housing bored out to handle a T04 turbine. The induction capability is awesome. I don't think the problem is with the turbo. I don't know the trim. I have asked Robert. He was supposed to forward the info to me, but has never sent it.

The next point is that our fuel injectors will not get us beyond 260 HP.....End of story. These must also be replaced.

I am running water injection for intercooling. If the Tec II is successfull I may add an air/water intercooler, if the front bumper gets built and I still have the money.

As for trannys, I believe the best setup would be a '98 WRX tranny, which will bolt up, with full dog gears. An ACT race clutch capable of handling 400 ft-lbs of torque. I think an STi would hold up very well with stock power but not with 400 HP. That is even more than the 22B version. I would love to do this, and would if I won the lotto. Instead, I am going to go the cheap route with a Level 10 upgrade. They boast being able to support 200-300% of the stock power with their internals. I guess I will be the guinnie pig.

[KEVINL]

now now. Just because I said I want the SVX to be fast doesnt mean drag car fast. I just feel that a car that should be producing 300HP+ could manage better than 15.3 in the 1/4 mile

[cdigerlando]

Kevin. I hate to tell you but you are not producing 300 HP or anywhere near that.

I don't think kevin and I are not building 1/4 mile cars. It is just a great proving ground to determine power gains.

All this being said, don't get me wrong. The turbo kit is great. Robert was the only one with the balls to build one. He put a lot of time into it. It fits perfectly. But like most kits more is necessary to make real gains. The only really wholistic kits are those developed by dynan and a few others. They are very expensive too. Just as much as mine will be. You just don't bolt on a turbo and expect huge gains.

Besides, if you are really serious about power a programmable ECU is a must even if you are running NA. So is fuel. KC talked about doing this with no turbo. This would also be an interesting route to take, and cheaper. And if you ever decided to go to a turbo, you could do it later with more programming.

Don't get discouraged Kevin. You have already taken the plunge. I'm sure these things will work out with engine management and fuel.

Shiv Pathak is running a Tec II on his 10:1 compression RS with a turbo and 550 cc/min fuel injectors. He runs a full dog box transmission. 0-60 in 4.1 seconds. The SVX sounds doable to me!

[KEVINL]

Hey chuck what kind of HP gains do you think you have

Well Roberts 2.5 RS kits have ran 13.9 with only a fuel pressure regulator
and he dynoed a Acura Legend with a turbo kit he built and installed and 65 wheel Hp was gained.

As soon as i get my car running I will dyno my svx and run it in the 1/4 mile

[cdigerlando]

I think the problem with the SVX is the limitations on the fuel, and the high compression. More conventional intake and exhaust mods will beef up the HP to its limit of fuel. Boost seriously complicates the timing issues and engine management.

The Acura and the RS may just have more room to play with due to slightly lower compression and more fuel availability. The FMU on the SVX is a good start. That is probably why you are somewhat faster than me. The really effective way to do this is with bigger injectors and engine management. I think you guys need to check out www.vishnuperformance.com

Tec II and injectors, Go with either infinity side feeds, 300 ZX turbo ('95 or '96 ONLY) or with Nismo injectors (550 for 300 ZX)
I am also checking with Dayle on stillens. I would prefer low impedance if I can get them to fit in my SVX side feed rails.

[KEVINL]

sorry to break it to you but the 2.5RS is 10-1 compression also.

[cdigerlando]

Yes, but I thought earlier model years were 9.5:1

[KEVINL]

true but the one that ran 13.9 was a 10to1 compression engine

[cdigerlando]

Yes. Shivs is a 10:1 as well. He is using an intercooler, a Tec II, fuel injectors in his own custom rail, and full dog gears in his gear box. Shifts like a tractor. He said he runs 0-60 in 4.1 sec. I don't know if this was on race fuel.

If I could tune to 300+ on street gas and 400+ on race fuel I would be satisfied.....for now.

[KEVINL]

Well I wish you luck on your project

I just want to know why the sorry 1/4 mile times

[cdigerlando]

Kevin:

I really wish you could get Robert to hook up with Shiv of vishnuperformance in CA. www.vishnuperformance.com

I really think he could help you guys out. Also Robert says he has been trained in PC tuning. I wouldn't even mind loaning you guys my Tec II setup and fuel injectors (when I get them). Or better yet maybe he has a used one you could try temporarily with some junk yard or otherwise used '95 or '96 300 ZX turbo side feed fuel injectors. (or infinities).

Last time I talked to Robert he said that the electromotive ECU is similar to a standard GM ECU and that he could put one together rather inexpensively. Maybe you should try this. I could send you the directions and get you a source to get stuff like the MAP, MAT, CLT, Knock Sensor, trigger wheel, and trigger sensor (both the wheel and sensor need some machine work to customize the installation.

The thing I like about the ECU I got is that it has mounted coils for distributerless ignition, and fires through 180 degrees. This should really help the power.

Anyway I will keep in touch

[oab_au]

Chuck.

>The thing I like about the ECU I got is that it has mounted coils for distributerless ignition, and fires through 180 degrees. This should really help the power.<

Can you explane what you mean by "fires through 180 degrees".

If you fire at, say 26 degrees, before TDC. max pressure is devoloped at about 15 degrees past TDC and the exhaust valve opens about 151 degrees later.
I don't see the point, unless I am looking in the wrong direction.

Harvey.

[svxistentialist]

Originally posted by cdigerlando
The thing I like about the ECU I got is that it has mounted coils for distributerless ignition, and fires through 180 degrees. This should really help the power.

Anyway I will keep in touch

Chuck

Best of luck with the mods. Is a Tec II a water injection system? I find it hard to believe you can force feed a 10:1 engine. Extra power made is related to the amount of oxygen burnt. Extra fuel needed is merely to burn it.

Your turbo must be on real low boost if heads are still stock 10:1, otherwise pinking would be crazy, and you would have to blow the gaskets. Water injection just keeps it cool to ease the pinking problem, does not add any power, other than it may allow you to run extra boost on a well optimised system. If you are not already running an intercooler, then do what ever it needs to put one in. Charge density is the secret to higher power, more oxygen through equals more power.

The turbo itself could be adding to the problem. Very high underhood heat will mean you are feeding the engine a lean diet. So you are adding higher pressures but a poorer fuel mix.

Put in the 300 ZX injectors and bolt on an intercooler, you should have a right good hp increase from that. You will need to determine that the stock ECU is not playing retard tricks with your timing. It will have been programmed for a radically different situation. Good luck with the level 10 also, and don't forget to at least go to the smaller wheel size for lower final drive.

Joe:)

[cdigerlando]

Right on in both on both counts.

The new ECU just has more fireing flexibility than the stock. That was my point.

[SVX10]

Everybody keeps saying that the SVX is too heavy, and it is. Why hasn't anybody done anything to reduce the weight? I can't say I have any great ideas about weight reduction (maybe remove rear seat?), but I think it would be worth looking into.
Mat

[cdigerlando]

That was what the CF hood was for. Did you get one? I don't know the exact weight reduction but I held my new hood in one hand easily. The original needs two people to manuever it around. That and removing the rear seats and replacing the fronts with race seats are the easiest and least expensive ways. My optima red top battery is real light too.

[Phast SVX]

Well, i dont have my SVX anymore, between dealer scuffs and the somewhat lemon scent my car was giving off i traded it in. I now own a 1995 Mitsubishi Eclipse turbo, and cdigerlando is completely correct. Those stock SVX injectors will flow 275cc...WHEN FLOWED. Not 10 years old. My stock injectors flow 450cc from the factory, and as of right now with my greddy BOV and Manual Boost cotroller im running 16.5 lbs of boost. That is the max for my little 2 litre engine with out upgrading the injectors and in tank pump. If you guys want to reach your goal, your going to have to start from the tank and work your way to the car, my GS-T Runs a 14.1 1/4mile right now, and just by upgrading the fuel system i could be running decent 13's on pump gas, god knows how much boost on racing gas. and The tiny TDO-25 in my car isnt anywhere near as large of turbine as your t3/4 hybrid. Just my take, but trust me, it is the truth. Before you do anything else to the turbo, take a look at fuel, after all o2 only assist in combustion.
phast

[Myxalplyx]

Any more information on this great post?

[FREESTYLER]

wait wait wait...
i have a 1991 Subaru SVX, all standard
last year out gearbox blew up(over heated and just crapped out) when we got it back, it didnt accelerate half as fast (putting it into 1st on the auto) we found out that after 1993 they changed the gear ratio's, so from 91 - 93 wecould pull 14.6 1/4 on the stock car
so, if you can find the older gear ratio.
and make sure you flush your radiator out, thats why ours blew up, hada block in it. + install the aux radiator..

[huck369]

I'd recommend getting a Legacy Tranny and rear diff, to have the Level 10 upgrade done to, this will net you lower gearing, thus putting the HP to the ground much better in the Somewhat heavy SVX:eek:
I believe the 4:11's of the Legacy will cut more off your timeslips than just the turbo did, and cheaper too.:)

[SVX10]

First off, I raced a 3000gt today from a dead stop...he got about 1' in front of me then I passed and won. But then I saw that it was a VR4, so he wasn't even racing...I barely won and he wasn't even racing. Hahaha. Ok, second, the only problem I see with the Legacy gears is the high RPM's. I know that's what happens, but 3000RPM at 60MPH is just too high for a touring car like this. Isn't there any intermediate gearing that could be done? Finally, somebody mentioned the Acura NSX and it's performance. Why can't the SVX be pushed like that? Is it all engine management? What's holding the SVX back (besides weight)? I've been looking at Comptech USA for a job, as some of you may know, and I've been reading up on their NSX work. Maybe they could offer some suggestions.

Mat

[wawazat??]

Yes, there are intermediate gears available. I know that a 3.90 ratio was used in certain models. I'd like to have a 3.70 or thereabouts.

The Comptech stuff is very cool. I saw a photo of there V-6 Accord supercharger and thought it would make a good launching point for our cars.

The things holding us back are weight, automatic transmission, weight, fuel delivery system, weight, gearing, weight, and weight. The 2002 NSX weighs in at 3153 pounds, approximately 400 pounds less than our car. It also offers 290hp from it's 3.2 liter engine and a much more performance focused set of gear ratios. I recall reading some time back that an addition of 100 pounds to a car will add 0.10 sec in the quarter mile. While its obvious that none of us here will be beating up on any NSX's in the immediate future, I think we can add considerable performace to the SVX but it won't be easy of cheap. If we wanted that we'd be driving WRX's or Mustang/F-bodies.

Todd

[Templar]

Well, a few things are holding the SVX back. Aside from power to weight ratio, the suspension, which is very nice and comfy, needs to be tweeked for performance. The good news is that Ohlins is working on a Coilover set up for Subarus that could be easily modified to fit the SVX. This coupled with a higher spring rate (say about 600 f/500 r) should really help a HUGE amount. Also we may fabricate some bigger sway bars as well to see what happens there. Having followed some SVXs through some twisty mountain passes in the last year, I can attest to the fact that the backside wallows in the curves.

Next, a five speed really does help. At the beginning of this thread it was mentioned that the guy with the Turbo SVX was only able to run in the 16 second range in the Quarter mile. Small car performance has a Normally aspirated SVX with a 5 speed that ran 15.33 at 93 mph. Okay that is still not a world beater, but it is better than it was. We are also going to be looking into different options on more appropriate gear ratios for the conversion as well.

And of course, as soon as we can get started on it, a supercharger will help the first problem mentioned above.

Kent
DNT Performance

[svxistentialist]

One of the UK members has modified his car for 5speed, and is in the process of adding a supercharger.

Can't give you any details, he is in the design stage and intends to go commercial. He is talking about 400hp through the WRX box. He is not a go-faster kiddie, and is not talking BS. He has more angles covered than I had thought of, everything thorough and professional. I like it so much, I may be in the market for an upgrade. All the mods will be under the bonnet, and I like the car to look stock, the way God[Guigiaro] made it.

Joe:cool:

[cdigerlando]

I would like to point out that I was going into detonation right around 5000 rpm when I ran a 16 flat. I did not detonate....the sensors retarded the timing, but the turbo is not done yet. I expect to be in the mid 13s when it is done with managment and intercooling.

As for a 5 speed, I think it is a great idea if you are not planning on pushing the HP much past 300. Even an STi gearbox is only rated for 280 HP on a 2700 lb car. We have a 3600 lb car and if you want to tune to 400 HP you will need a hardened gearset like a MRT ($3200 just for gears). And if you beyond about 400 HP you will need a full dogbox. Dogbox.....yuk! The level 10 rebuild was $4500 and will handle up to 700 HP.

That said, it would be nice to see a mildly tuned SVX with a hardenend sycnro gearset, running high revs with a new cam profile and beefed up rods w/forged aluminum 11:1 compression pistons. High rpm reving would not produce the torque that a turbocharged car would. You might get away with close to 400 HP with this setup.

As for the suspension, I agree that a thicker sway bar would benifit the car immensly. In fact if you plan on producing them there was some interest from people to buy them. I think a rear sway bar and crossbar setup would do a lot to reduce understeer. You really need to try the Koni/GC setup. I have it on my car. It is simply awesome. The car grips the road and holds curves better than my WRX! Just does not have the turn radius.

Where are you located? When I get my car finished you should come by and check out the goods. Nothing better than a test drive. I am in Orlando, FL.

[Templar]

We are in Asheville NC, but our project car is going to be located in Greenville SC. Perhaps the next time we have a big Southeast Subaru Owners club meetings, we won't overlook this board. Actually the fellow who will own the project car organized the huge Subaru meet we just had at The Dragon (http://www.tailofthedragon.com) but he and I discovered this board about ten days too late, but we have both been big fans of the SVX for a long time.

Our biggest time constraint right now is finishing the Stage I kit for the 2.5 liter. Once that is done, Stage II will be relatively easy since everything is already worked out for it as well, it is more a matter of finishing a strong enough brakcet design that will fit. Once all that is complete, and Porter has his SVX in hand, then I can start work on the SVX kit. It shouldn't take as long as this initial product.

We can probably get Addco to make a sway bar for us pretty easily, but they require a minimum run of 25 pieces. If it is a possibility, I can check it out. I have a very good friend who works closely with them.

[cdigerlando]

Sounds neat. I would be interested to hear what you are doing to the 2.5. Closed deck? Forged Rods? Forged Pistons? Cams? Valve trane? Cobb tuning has a Stage I II and III shortblock for the 2.5. I would be interested to hear how yours is built up. I would also be interested in a semi closed deck on my SVX engine with some oil line boring ect. Cams heads etc. Lower compression of course. This will be stage II of my project. Now if I could just finish stage 1! If you finish your project before I am ready to rebuild, and the price is right, I would be interested in haveing some work done on my car. I love Ashville!

[Templar]

Oops, sorry that read a little strangely. The Stage I for the 2.5 is a first stage supercharger kit. It will be designed for low to moderate boost levels (6 psi MAX) and use stock engine components. It will include all the mechanical and electronic management and fuel components to run reliably and safely.

Stage II will be a slightly higher boost range (8 psi) and include a few other goodies. This will be around a short time after the Stage I is available. Once this is done I will probably begin work on the SVX project. It will probably be very similiar to stage I of the 2.5 kit in terms of boost levels and management.

Once this is done I do plan on approaching Paeco in Alabama to build one of their SRE engines with a lower compression (probably 9:1) in a 2.5 and really turning up the boost. (we'll have to wait and see how high, but I am hoping to go up to 12 to 16 lbs of boost at redline, which should be around 7000 rpm at that point) After that experiment is done, Porter has expressed interest in having something similiar done with an SVX block.

If everything goes well, within the next year and a half to two years we should have a 2.5 RS putting out around 350 supercharged bhp and an SVX close to 400.

[SVXtypeR]

Originally posted by wawazat??
The things holding us back are weight, automatic transmission, weight, fuel delivery system, weight, gearing, weight, and weight.

Todd

ROTFLMAO!!!!

[solarsvx]

hello cdigerlo i wouldnt mind checking out your setup i live in orlando florida here also , actually there 3 other svxs i been talking to here in orlando, but i would love to check the svx out and what u have accomplished. email me directly if u can james@far.org

[Porter]

I'm still trying to find an SVX in good condition with less than 80k miles for less than $6500. Anybody? Beuller? Beuller?

I'm looking for a later model if possible, the auto seatbelts drive me nuts and add weight... :p

[solarsvx]

hey porter il sell u mine if the price is right, => its a 92 with 85k on it its perfect in every way , i spent over 400 just haveing every little dent and mark took out, its silver with black top, its the best shape svx u will ever see => but im looking to get 8,000 for it,, why 8,000 i just put 18" rims by 8" wide 2 piece.. and kenwood double din cd cassete navigation radio, with upgraded infinit speakers, didnt want to sell he soo soon but if the price is right ill let her go , =>

[Porter]

<---drooling....

Got Pics? Email me at jasonporter3@charter.net

[oab_au]

Originally posted by Templar
Well, a few things are holding the SVX back. Aside from power to weight ratio, the suspension, which is very nice and comfy, needs to be tweeked for performance. The good news is that Ohlins is working on a Coilover set up for Subarus that could be easily modified to fit the SVX. This coupled with a higher spring rate (say about 600 f/500 r) should really help a HUGE amount. Also we may fabricate some bigger sway bars as well to see what happens there. Having followed some SVXs through some twisty mountain passes in the last year, I can attest to the fact that the backside wallows in the curves.

Kent
DNT Performance

Hi Kent :) , 600"lbs front 500"lbs rear!!!!!!!!

Could be a bit over kill. A 500% increase could be a BIT HARD!

The standard rates are front 140"lbs, rear 109"lbs. It's a long travel suspension.
Harvey.
:(

[Templar]

It would only be terribly hard if it weren't a matched rate with the struts. I have ridden in a WRX with JIC FLT-A2 coilovers that had 450 lbs fronts and 400 lbs rears. The car rode great. It was almost, but not quite, as compliant as stock, but once it hit the curves, it stayed flat and handled like a go kart. Very nice. The extra 450-500 lbs on an SVX might would probably need the super-heavy rates. The coil overs that FLATT racing in Japan make for the SVX have 661 lbs/inch front and 437 lbs/inch rear rates. The spring rates that I described above, on the right struts, would provide a more compliant ride than these and have less understeer due to the closer relationship in rates between front and rear rates.

[cdigerlando]

Maybe dayle can chime in and tell you what my GC/eichbach coil over rates are.

[oab_au]

Originally posted by Templar
It would only be terribly hard if it weren't a matched rate with the struts. I have ridden in a WRX with JIC FLT-A2 coilovers that had 450 lbs fronts and 400 lbs rears. The car rode great. It was almost, but not quite, as compliant as stock, but once it hit the curves, it stayed flat and handled like a go kart. Very nice. The extra 450-500 lbs on an SVX might would probably need the super-heavy rates. The coil overs that FLATT racing in Japan make for the SVX have 661 lbs/inch front and 437 lbs/inch rear rates. The spring rates that I described above, on the right struts, would provide a more compliant ride than these and have less understeer due to the closer relationship in rates between front and rear rates.

The only way these would not be "terribly hard", would be if they were fitted to struts on a truck.

If making a car handle consisted of fitting springs so hard that they don't work, It wouldn't be the science that it is today.

If the roads were flat and smooth, we wouldn't need suspension. Unfortunatly they have bumps. This is what the springs are for. When the wheel hits a bump, it moves up, the spring compresses so that the body stays on the same plane so that the spring pushes the wheel back down on the other side of the bump.

With hard springs fitted, when a bump is hit, the wheel will move up, but instead of all the movement being contained in the spring, movement will be transmitted to the body. Moving it up, when the wheel has to move down on the other side of the bump it will not have the capacity to keep traction with the ground because the body is holding it up removing weight from the wheel.
Any sort of bumpy road would have the car skipping around.

Springs of the rate that you recommend, would lead to instability and loss of traction at speed. As this would be dangerous at the speed that this car does, I would strongly recommend that they are not used.
We don't want somebody suing somebody, in the event of a mishap, do we ?

Harvey.

[Templar]

Okay, someone obviously either knows nothing about suspension tuning, or has never ridden in a car with high spring rates ON STRUTS THAT WERE DESIGNED FOR THOSE RATES .

I can tell you because I have done it, driven it, installed it, and raced it. If you have a heavy enough car with struts that are properly damped for those rates, the ride IS NOT harsh. Perhaps if you have only ridden in Rolls Royces your entire life you might consider it harsh.

Spring rates on Tein coil overs for R34 and R33 Sklylines (which weigh very close to the same as an SVX by the way) range from 448 lbs/inch front and rear, to 671 lbs/inch front and rear, depending on which suspension you are looking at. The 448 lbs/inch models are the street/track models.

I live in the real world. The one where we don't judge a suspension based solely upon spring rates. A suspension is a complete unit to be tuned as a complete unit.

[MoreIBNR]

I tend to agree with Harvey - I don't care about the struts, if the springs are 500 lb rate, it will take 500 lb of effort to compress them 1 inch. If the original springs were 140 lb, that's almost 4 times the effort. If a particular bump in the road caused the stock springs to compress 1 inch, the after market ones will only compress 1/4 inch. That has to transfer a lot more impact to the occupants of the car - regardless of the struts. All the struts do is generally control the rebound of the spring and keep it from continuing to bounce.

Originally posted by Templar
Okay, someone obviously either knows nothing about suspension tuning, or has never ridden in a car with high spring rates ON STRUTS THAT WERE DESIGNED FOR THOSE RATES .

I can tell you because I have done it, driven it, installed it, and raced it. If you have a heavy enough car with struts that are properly damped for those rates, the ride IS NOT harsh. Perhaps if you have only ridden in Rolls Royces your entire life you might consider it harsh.

Spring rates on Tein coil overs for R34 and R33 Sklylines (which weigh very close to the same as an SVX by the way) range from 448 lbs/inch front and rear, to 671 lbs/inch front and rear, depending on which suspension you are looking at. The 448 lbs/inch models are the street/track models.

I live in the real world. The one where we don't judge a suspension based solely upon spring rates. A suspension is a complete unit to be tuned as a complete unit.

[Porter]

I agree with Templar, based on what I have seen and felt as both a passenger and driver of a number of vehicles with high end suspensions.


I'm guessing most of you are not familiar with either progressive rate springs or linear/helper spring combos?

The basic road jounce at +/- 1in travel is absorbed by the helper spring or the weakest coils of a progressive spring.


To throw more perspective on this as well, realize that a truly high end strut will control a 600lb/in spring far better than the stock strut controls the stock spring.

Thus, when you hit a pebble in the road or a bridge seam or an asphalt ripple.... The strut allows the instantaneous compression of the spring while preventing instantaneous ("jitter") rebound. This prevents the obstacle from being felt as a "bang" through the body of the vehicle. The strut actually soaks up the impact.

Truly high end struts (like the Ohlins, JIC, or Leda) actually are designed with different valve release rates for low-speed and high-speed compression. Thus, a comfy ride while cruising and extreme agility while cornering. Some models even have separate adjustments for low and high speed compression.


I doubted it too until I took a ride in an RS with a set of Leda coilovers with 400lb spring rates! It blew me away how compliant it felt over bumps. It was smoother and softer than the stock suspension, but when thrown into the corners, whoa momma! Flat, tight, and instantly responsive.

;)

[svxjoe]

But the cream was a black Corvette[last model] tuned by a guy called Lingenfelter I think. It also sensibly had uprated suspension and brakes, and ran on huge Fikse chrome wheels which were a bit OTT, but worked. This car could go 0-100-0 in about 11 or 12 seconds. Now that is serious $hit!!


Just recently Lingerfelter, has beefed up a Corvette with twin turbos. It is the fastest street legal car at 226 mph. It also had all the other little (or should I say major) upgrades of the suspenion, brakes, etc. Price of the Corvette as tested.....:eek: $114,000. A bit much for a Corvette but hey it will destory any Ferrari or Lamborghini:)

((Well, I thought it was pretty interesting.))

[MoreIBNR]

You may be right for variable rate springs. My comments were in reference to constant rate springs as I don't remember any mention of variable rates - just 500 lbs.

Originally posted by Porter
I agree with Templar, based on what I have seen and felt as both a passenger and driver of a number of vehicles with high end suspensions.


I'm guessing most of you are not familiar with either progressive rate springs or linear/helper spring combos?

The basic road jounce at +/- 1in travel is absorbed by the helper spring or the weakest coils of a progressive spring.


To throw more perspective on this as well, realize that a truly high end strut will control a 600lb/in spring far better than the stock strut controls the stock spring.

Thus, when you hit a pebble in the road or a bridge seam or an asphalt ripple.... The strut allows the instantaneous compression of the spring while preventing instantaneous ("jitter") rebound. This prevents the obstacle from being felt as a "bang" through the body of the vehicle. The strut actually soaks up the impact.

Truly high end struts (like the Ohlins, JIC, or Leda) actually are designed with different valve release rates for low-speed and high-speed compression. Thus, a comfy ride while cruising and extreme agility while cornering. Some models even have separate adjustments for low and high speed compression.


I doubted it too until I took a ride in an RS with a set of Leda coilovers with 400lb spring rates! It blew me away how compliant it felt over bumps. It was smoother and softer than the stock suspension, but when thrown into the corners, whoa momma! Flat, tight, and instantly responsive.

;)

[oab_au]

Originally posted by Templar
Okay, someone obviously either knows nothing about suspension tuning, or has never ridden in a car with high spring rates ON STRUTS THAT WERE DESIGNED FOR THOSE RATES .

I can tell you because I have done it, driven it, installed it, and raced it. If you have a heavy enough car with struts that are properly damped for those rates, the ride IS NOT harsh. Perhaps if you have only ridden in Rolls Royces your entire life you might consider it harsh.

Spring rates on Tein coil overs for R34 and R33 Sklylines (which weigh very close to the same as an SVX by the way) range from 448 lbs/inch front and rear, to 671 lbs/inch front and rear, depending on which suspension you are looking at. The 448 lbs/inch models are the street/track models.

I live in the real world. The one where we don't judge a suspension based solely upon spring rates. A suspension is a complete unit to be tuned as a complete unit.

Hang about Kent !

Don't get excited. Were only talking about suspension mods that are applicable to the SVX.

You are plucking out all sorts of rate combos that Impressa, Nissan and Evos use. Then suggesting they be used on a SVX.
Tits do wonders for the female form but, don't work as well on the male version! :rolleyes:

I know what you are saying, but we are coming from different directions. The Street skaters that you are talking about, and the SVX, could not be further apart.

The type of suspension that you are in to, is for smooth streets or circuits, they don't have bumps bigger than a pebble or join in the 'hot mix' (is that what you call it up there), 1.5" of movement is enough. If there are no bumps suspension travel is not needed, so the spring rate is increased to the point of no movement.

The SVX is designed to be a high speed Grand Tourer, cruising at 120mph all day on any road type, is it's world. For a car like this long travel suspension is essential.

The higher the speed the car runs at, the more the body wants to stay on the same plane, doesn't want to move up or down. Rises or dips in the road have the suspension moving to it's full limit. If this travel is 1.5" instead of the 6+" that it's got. It would leap off the top of the rises and plough into the ground in the dips.

It's horses for courses, a street skater, the SVX is not, it's geared too high for that. Though nothings impossible, with some of the blokes that are in this club it could happen. :)

Kept it cool Kent, we can still be friends, :cool:
As far as driving around in Rolls Royces,:D :D :D You don't know Australians. :D :D :D
Harvey.

[Red SVX 92]

I think the GC springs are 450 front, 300 rear. Personally, it's a little bit harsher than stock, but not by much, and the cornering feels a lot nicer.

[Trevor]

Templar,.

You state -- Ò someone obviously either knows nothing about suspension tuning, or has never ridden in a car with high spring rates ON STRUTS THAT WERE DESIGNED FOR THOSE RATES. Ó Also Ò I have done it, driven it, and raced it Ò. You must also wear a large sized hat.

You have made statements which defy the laws of basic engineering. No spring damper ( A strut in my book is the complete assembly which in a McPherson set up includes the spring ) can make a hard spring soft. I will not use the term Ò spring rate Ò as this involves further complications in the engineering sense but does not alter the basics. I would be interested to have your definition of Ò spring rate Ò.

I too know a little about suspension tuning first hand. Harvey has made the point. that maximum stiffness does not result in maximum cornering performance and spring dampers can not reduce basic spring stiffness. This is an engineering fact and your comments directed towards him appear patronizing to say the least and are not based on fact.

There is an additional factor which involves input to the driver and response to the drivers output. A really stiff ride might be interpreted by the boom boom brigade as cool but does not necessarily translate into maximum cornering performance. In my experience most suspension specialists of the retail variety are aligned with the hoon sector of the buying public who may try a bit of a drag in a straight line but have never got anywhere near nine tenths in a fast corner.

I also note that you Ò live in a real world. The one where we donÕt judge a suspension based solely upon spring rates. A suspension is a complete unit to be tuned as a complete unit Ò. With this I agree wholeheartedly and I am sure Harvey does too, but your statement places you in a glass house so that you must expect some stones.

A short time ago I posted a thread regarding a quick rack for the SVX with which I am sure I could make my standard car which is like Harvey's RHD
go more quickly on a give and take road or racing circuit than another with messed up suspension. It was interesting how few replies there were in regard to this essential requirement if the car is to be turned into something truely quick.

You should note that my car and a LHD is different in several respects including suspension settings. We are talking about market preferences here and the RHD is more of a drivers car. Harvey is well versed in the differences and can explain if need be. I like Harvey do not ride in a Roller and I would point out that it is you who are in the land of the traditional boulevard cruiser.


Going back further in the posts I note that you have followed some SVXes through twisly mountain passes and can attest the fact that the backside wallows in curves. I can attest too from observing many cars at very close quarters when participating in motor racing that many of the fastest do exactly that in tight corners and by doing so keep all their feet on the ground. Many of the fastest I have driven have appeared very hairy indeed but have in fact been quicker than another which has gone round as if on rails. Your observation in fact means nothing as the truth can only be learned from the drivers seat.

As harvey has said keep it cool and polite.

[svxistentialist]

is good advice here.

People are coming at design improvements from diametrically opposed corners, and propounding that they know the Truth.

In car terms, the Truth is, everything works for different surfaces and different drivers. Nothing is the Best.

The current Corvette in my opinion is one of the best performance deals in the world. Outstanding power to weight, very high skid pan lateral g figure, what more could you want? Reason they don't sell here or in the UK very well?? Lack of suspension travel. They crash out over the sort of bumps we take here to be normal.

You guys must ride all day in the States on billiard table surfaces. Circuit racers can up the poundage of their springs, secure in the knowledge there are no dips or bumps to put the body on the bump stops. Over here, hard springs equals hard ride. No fun travelling all day at 120. Much gritting of teeth each time your car lands.

The same basic truth applies to bikes, which as most of you know, are faster than the fastest cars. Bikes with track suspension can be passed on bad roads by lesser machines with long travel set-up, even though the hard set-up bikes have masses of power and all the street cred. Fast riders know this and just accept it.

The SVX travels very much like a Jaguar. Grips like a good'n, but smooth because of long travel suspension. Exemplary body control. When you boys talk about the suspension unit working, and being designed as a unit with the strut, you are correct, but it's not the whole truth. Chassis designers are not solely concerned with wheel movement and lack of sway you know. The total design ethic also incorporates body movement, yaw, chassis flex, unsprung weight etc etc. Upping the spring poundage or rates is changing one parameter only in what is a very fine body control system. Be prepared to live with your silk purse changed to a sow's ear, at least on the sort of roads we live with.

Be cool Yolanda

Joe:)

[Trevor]

Thanks Joe,

What I am debating here is engineering facts and truths if you like and there is no denying no matter from what angle the subject is approached. that facts are facts in respect of physics.

I agree with your analysis of various aspects of suspension design and all design must be a compromise to be sure. The major contention which has been put forward with great gusto is that a spring damper can reduce the load required to compress a stiff spring and soften the ride which is a complete fallacy. If a spring is stiff it is stiff and there is no magic match with any other component that can change that.

Spring rate = force divided by deflection and this can not be affected by a spring damper. What is more the whole system has a fixed natural frequency rate which can only be damped and not changed by a spring damper. The manufacturers of after market telescopic dampers put out a load of hype giving the idea that their magic unit can work wonders but they can not defy the laws of physics.

Yes Joe you are spot on when you say that the suspension system must be considered as a whole but Harvey has been rubbished in no uncertain manner in respect of a specific point which he has made but he is in fact correct.

Kind regards, Trevor.

[2edybrd]

Hi Everyone, I hope you don't mind an F-body guy jumping in here, but I was reading this post and wanted to give my opinion. First, I don't think you guys realize what a great handling car you already have. Before the Trans-Am, I owned a '92 SVX that I put over 100,000 miles on. I beat the living hell out of that car. The only thing that I really thought needed improvement on the suspension was the way the car rolled in the corners. Bigger sway bars will give you real improvements in corners. The SVX I owned I bought from new. I wanted to know as much as possible about the car before taking a 28,000 dollar chance. Motortrend, Car and Driver, and Autoweek all did pretty extensive reveiws on the cars handling. All agreed that better sway bars would improve the car immensely. If you want to upgrade your springs, you don't really need to go go much higher than what you have. The T/A weighs in at around 3300 LBS. I'm running progressive rate springs front and rear at 300 - 450# f/ 115 - 185# r. My swaybar in the rear has stayed at the stock size while the front bar was replaced with about 5 mm extra diameter. Sometimes all you need to do is replace the bushings with polyeurathane (sp.) and that alone will make a huge difference. What are the rates on your springs again? Finding a spring with maybe 50# more rate could help alot. As far as turbo charging goes, I'm more familiar with V-8's. I know for the LS-1 engine that larger combustion chambers help by lowering the compression and allow the turbo to be more efficient. Also, how much does the intake manifold flow? Injectors? Fuel pump? What is the computer doing with all this extra airflow? Is it pulling timing from the engine? Is it pulling fuel? 60 -90% increase in wheel horsepoweris pretty normal with a turbo set-up. But tuning the engine is very, very,very important as well. Thanks for putting up with my long post.

[Templar]

Hello all,

Sorry I got a little perterbed earlier, but I I had read something into Harvey's earlier post that hadn't actually been there.

Now back to it. Yes, Trevor, a strut cannot change the rate of a spring. However I do disagree with your assessment that 600 lb f/500 lb r spring rates would be super stiff on an SVX. These rates are still a ballpark I am think of, we won't know for certain what the best rates will be until Ohlins USA puts the car on its shock dyno and gives us some ideas.

Would they be stiffer than stock? Yes

Would they be uncivilized and harsh? No

I never stated that you could change a spring rate, I did state that with aproppriately tunes dampers the spring reacts in a manner that it is suppose to.

An example"

My current suspension setup. STi Version 5 struts with 5Zigen progressive springs. Rates are 169-226 front and 80-180 rear. My car ride decently, but it is nothing to rave about. 25mm front sway bar and 24 mm rear. The car handles and corners extremely well, I have been told it is the best cornering Impreza in the US, but the ride quality is not as good as stock.

Scooby Souths car. Identical 2000 2.5 RS with stock 19mm front sway bar, 22 mm rear. LEDA option B coil overs with 400 lb front and 350 lb rear spring rates. His car will handle closely with mine. The car is smoother, but I have better turn in and stability due to the sway bars. However, his car rides at least as smooth as stock if not a little smoother.

Now granted, we are not talking about putting 900 lb front and 800 lb rears on the SVX. That WOULD be stiff.

As far as the comment about aftermarket strut companys. We will be using Ohlins coilovers on the SVX project. If you have never heard of Ohlins then you should check out some info about them on a search engine. 22 of the cars at Indy this year ran on Ohlins. Most of the World Rally cars use Ohlins designed struts.
Tommi Makinen won 4 World Championships on Ohlins. They are a bit different from most suspension companys.

Anyway, we will wait till the car gets to that point and put it on their "chassis torture machine" and see what they come up with.

Kent

No offence meant to anyone on the board.

[svxistentialist]

Sounds like you have a lot of experience with Scoobys Kent, and I am sure no-one took any real offense. Everybody likes a lively debate, but there is no benefit to denigrating another's opinion.

We don't get those 2.5 engines here, Imprezas are all 2.0 litre turbos. Don't have experience of them myself, but a friend who rallies cars says there is nothing like them in terms of grip and capability and body control, allied to a [relatively] smooth ride and body control.

This same guy was impressed with the SVX as a road car. However, if you press a big heavy car to rally speeds, you will find the limits, and the penalty for the weight.

Graham in the UK was very enthusiastic about upgrading the suspension along the lines of the Impreza WRX, but maintains the Japanese version is superior to the standard British one.

I am not against improvement if it was possible, but I am happy to accept as a trade-off the lack of low speed bump-thump over rough surfaces for absolute flat tracking at high speed.

So it swings the tail at high speed? Watching tails swing has been a hobby of mine for a long time now.

Joe:) :D

[Trevor]

This thread has included some lively debate and as a result contains some interesting and worthwhile information so lets have more of these.

A round of thanks to all who have participated is in order, so cheers to all.

Trevor.

[oab_au]

Originally posted by Templar
Hello all,

Sorry I got a little perterbed earlier, but I I had read something into Harvey's earlier post that hadn't actually been there.

Now back to it. Yes, Trevor, a strut cannot change the rate of a spring. However I do disagree with your assessment that 600 lb f/500 lb r spring rates would be super stiff on an SVX. These rates are still a ballpark I am think of, we won't know for certain what the best rates will be until Ohlins USA puts the car on its shock dyno and gives us some ideas.

Would they be stiffer than stock? Yes

Would they be uncivilized and harsh? No

I never stated that you could change a spring rate, I did state that with aproppriately tunes dampers the spring reacts in a manner that it is suppose to.

An example"

My current suspension setup. STi Version 5 struts with 5Zigen progressive springs. Rates are 169-226 front and 80-180 rear. My car ride decently, but it is nothing to rave about. 25mm front sway bar and 24 mm rear. The car handles and corners extremely well, I have been told it is the best cornering Impreza in the US, but the ride quality is not as good as stock.

Scooby Souths car. Identical 2000 2.5 RS with stock 19mm front sway bar, 22 mm rear. LEDA option B coil overs with 400 lb front and 350 lb rear spring rates. His car will handle closely with mine. The car is smoother, but I have better turn in and stability due to the sway bars. However, his car rides at least as smooth as stock if not a little smoother.

Now granted, we are not talking about putting 900 lb front and 800 lb rears on the SVX. That WOULD be stiff.

As far as the comment about aftermarket strut companys. We will be using Ohlins coilovers on the SVX project. If you have never heard of Ohlins then you should check out some info about them on a search engine. 22 of the cars at Indy this year ran on Ohlins. Most of the World Rally cars use Ohlins designed struts.
Tommi Makinen won 4 World Championships on Ohlins. They are a bit different from most suspension companys.

Anyway, we will wait till the car gets to that point and put it on their "chassis torture machine" and see what they come up with.

Kent

No offence meant to anyone on the board.

No problems Kent :)

We all have our own opinions on making a car or bike handle.
I like to drive or ride it to analyse the problem, then to make a change that helps that aspect of the handling without upsetting anything else.

As for the SVX, I drive it, as it was designed for, as a high speed tourer. In that respect it doesn't need too much of a change. May be a bit more compression damping in the front, a bit more rebound damping in the back and about 25% more rear roll bar.

For other types of driving, I use a different car.

In Australia we are no stranger to the WRX, we have had it since it's launch in 94. Most of it's development took place here in Oz.
We have had all aspects of it including the unobtainable Sti 22B.

Ohlins are also well known and respected here. I have used them on race bikes but they are not cheap. Konis even with only rebound damping, can be made to work well, by changing the oil viscosity, to suit the desired compression damping, then adjust the rebound back, to obtain the same rebound damping.

I have found that the more adjustments the suspension has the more people set it up wrong.

Anyway push on with your Ohlins development. We could all use another option in the way of struts.

Harvey.

[Templar]

Hey cool,

I am glad that we all got together and are friends again. Like I said, I originally misread something in Harvey's post that I took as a stab, so I stabbed back, I apologize.

Anyway, it is good to see that we have agreed to disagree. I will be the first one to admit that I don't know EVERYTHING. hehehe.

Actually, it is funny that you mentioned the rear roll stiffness. One of the first things we plan on doing once we get an SVX in our hot little hands is to try to get a custom fab on a bigger rear anti roll bar. There is a very prominent sway bar manufacturer within an hour of us, and they have been known to make custom runs, but they do normally require a minimum run of 25 units. We may try to get a Group Buy together for this if there is interest.

Sincerely,

Kent Burgess

[Zeppelin]

Originally posted by Templar
Hey cool,
There is a very prominent sway bar manufacturer within an hour of us, and they have been known to make custom runs, but they do normally require a minimum run of 25 units. We may try to get a Group Buy together for this if there is interest.



How much do you think they'd be charging for this? If it's cheap enough, count me in!

[oab_au]

Originally posted by Templar
Hey cool,

I am glad that we all got together and are friends again. Like I said, I originally misread something in Harvey's post that I took as a stab, so I stabbed back, I apologize.

Anyway, it is good to see that we have agreed to disagree. I will be the first one to admit that I don't know EVERYTHING. hehehe.

Actually, it is funny that you mentioned the rear roll stiffness. One of the first things we plan on doing once we get an SVX in our hot little hands is to try to get a custom fab on a bigger rear anti roll bar. There is a very prominent sway bar manufacturer within an hour of us, and they have been known to make custom runs, but they do normally require a minimum run of 25 units. We may try to get a Group Buy together for this if there is interest.

Sincerely,

Kent Burgess

Yes Kent , the rear suspension has been compromised, in respect of the cars ability to carry rear seat passengers and luggage in the boot.

Load the boot up with luggage, the floor is quite high, and the roll center rises, to cause a bit of roll and rear lift. A bit more rebound damping will delay the lift. A stronger rear roll bar, will cause the outside, loaded spring, to become stiffer as the bar adds resistance from the inside spring.

Too strong a rear bar will make the car waddle over uneven ground, with the loss of the independence of the rear wheels.

Now If I could just convince my best mate to leave the rest .of the house behind, when we go tripping. It would not need any mods. :D (fat chance)

Harvey.

[Templar]

Just going by what I know that they have charged for other runs of bars, I would guess that a 1 inch (25mm) bar would run somewhere in the $150 to $175 range with Polyurethane bushings included.

[cdigerlando]

I really really wish you guys could try the Koni/GC suspension. I do not like the stock SVX suspension at all! The front dives and bottoms. There is an enormous amount of understeer. After I did the koni/GC setup, I was thrilled to see that my car now handles like a beast. No more roll, no more understeer, no more dive. The car now handles like a sports car.

I like grand touring cars too. I do not like understeer and diving to the point of bottoming. This is unacceptable to me. And that is why I modified the suspension.

[Porter]

The GC systems are decent, but are not in the same ballpark with a true integrated adjustable coilover.

GC uses a stock type strut and spring with a height adjustment collar... far different from the much smaller diameter spring, huge strut body, and integrated height adjustment threading of a real system.

http://www.ohlins.com/images/product_photos/OHL_Mit_Evo_rally.jpg

http://www.amfmotorsports.com/update2/tune/desktopimgs/shock_800.jpg

[Templar]

Darnit Porter,

Now not only have I been trying to hook up on IM with you all week, but you had to go and post those porno links. hehehe

[deligeds]

I too would be interested in a rear sway bar, but I'm afraid you won't have a chance of getting 25 orders in a group buy. A few months ago, there was talk of a similar group buy, and if I remember correctly, there were 10 or 15 probable buyers. It never happened, but I can't imagine you'd get much more interest than that. Anyway, if it ever happens, count me in as well.

[Zeppelin]

Originally posted by deligeds
I too would be interested in a rear sway bar, but I'm afraid you won't have a chance of getting 25 orders in a group buy. A few months ago, there was talk of a similar group buy, and if I remember correctly, there were 10 or 15 probable buyers. It never happened, but I can't imagine you'd get much more interest than that. Anyway, if it ever happens, count me in as well.


*shhhhhhh* they aren't supposed to know that! ;)

but seriously, maybe some people will want one after the finished product is there.. I know some people won't commit to anything until after they see a finalized product! Maybe Dayle would take 5 sets or so to sell in his shop?

Definitely count me in for this deal! $150 is pretty cheap for a suspension mod! :)

[cdigerlando]

The Eichback springs used in the GC coilover are very similar to the spring/strut set you show. The struts are probably not of that caliber though.

[Porter]

Every GC setup I've ever seen used a spring that was of the same diameter as the stock spring, and a strut that was essentially of the same design as stock but with adjustable valving.

Are the SVX systems different from other GC setups? The springs in the pic I posted are roughly half the diameter of stock.

[SVXtypeR]

Originally posted by Porter
Every GC setup I've ever seen used a spring that was of the same diameter as the stock spring, and a strut that was essentially of the same design as stock but with adjustable valving.

Are the SVX systems different from other GC setups? The springs in the pic I posted are roughly half the diameter of stock.

When I originally designed the GC/KONI combo (with the assistance of TONY for spring rates on the dual setup) the idea was for a coilover-type setup which ment 3.5inch ID springs, so it looks basically like a cobbled-together version of the pics you showed (there was nothing ready-made back then for the SVX).

I'm not sure how others have interpreted the design since then, but you can see pics of my first conversion on www.subaru-svx.COM. Look for pics of the Washington DC Haines Point meet (Jester took a pic up in the wheel well, it's kinda' blurry, but it gets the point across).

Any more questions (spring rate, ride, etc...), feel free to shoot away.

[Myxalplyx]

This is a very good thread on turbos, suspensions, etc. I just thought it would be a good bump for some.

[cdigerlando]

The GC springs have a much smaller diameter than the stock setup. The struts are adjustable and at their softest setting are much stiffer than stock.

[Myxalplyx]

Originally posted by svxistentialist
Which reminds me, a far cheaper option. Buy the rebuilt Legacy box from Randy. Fit it and also fit the rear Legacy diff so you can run it 4wd and don't have to be pulling fuses and stuff. This will give you a lower final drive in all the gears, you can make all that torque work for you.

The piece de resistance, run with a set of race wheels, 15" set running 205 rubber should be just right. These will have enough grip to get away, but will have a nice bit of a lower rolling radius to drop your final drive another little bit. Use high traction race rubber such as Yokahama, they won't last long, but you won't want them to.

This should be a cheap way to drop a second or two, especially if you are already running a turbo.

Joe

Joe,

This is EXACTLY what I would do if I got an SVX. Higher stall speed torque converter, valve body (hydrosystem) job, tranny cooler, synthetic tranny fluid and Legacy 4.44 gears.

My question is (to anyone) has anyone on the board installed Legacy 4.44 differential gears into their SVX? I think that would be awesome. I'd never get to utilize speeds above 100mph anyway so I wouldn't mind the higher rpms during cruising. If anyone knows of anyone who has done this, could you please provide me with an email or what not so I could reach them? Thanks!

[1994SubaruSVX]

all the gc's for the svx that i have seen have been smaller. especially if you have the koni setup.

[svxistentialist]

Originally posted by Myxalplyx


Joe,

This is EXACTLY what I would do if I got an SVX. Higher stall speed torque converter, valve body (hydrosystem) job, tranny cooler, synthetic tranny fluid and Legacy 4.44 gears.

My question is (to anyone) has anyone on the board installed Legacy 4.44 differential gears into their SVX? I think that would be awesome. I'd never get to utilize speeds above 100mph anyway so I wouldn't mind the higher rpms during cruising. If anyone knows of anyone who has done this, could you please provide me with an email or what not so I could reach them? Thanks!

Randywas running for a long time with a Legacy tranny installed. As I understand it, he may have pulled the fuse, and been running in front-wheel drive mode, but the front diff for sure was Legacy based. I don't think it gave major problems, other than not matching the rear diff. Do a PM to Aredubjay, he will tell
you the story.

For myself, with inherent auto problems on mine, I may well be the only member who has run his car with only third gear, which is direct drive. Last year I drove like this from Feb to Sept, and this year from Jan to now. At highway speeds, you run 3 to 4 thou, no big deal. The bad rear bearing I have is way louder than the engine tranny sound you hear. So dropping final drive should be no real penance.

Joe:)