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-   -   ECUtune Stage 2 version 3 ( 2v3 ) (https://www.subaru-svx.net/forum/showthread.php?t=27380)

longassname 07-19-2005 12:14 PM

Quote:

Originally Posted by Earthworm
I wonder if this would help my situation. My engine won't rev all the way to 7400 rpm. I'm lucky to reach 7000 (w/stage I). When it reaches this limit it starts bucking but not like a normal rev limiter.

My dad's 95 does the same but gets an additional 200 rpm.

In 4th gear I reach 135mph before it starts bucking.


That could just be an inaccuracy in your tach or it could be something else. Subafreak has the same problem but at 6000 rpms and he used to get over 7000. We're trying to figure out what is going on now. He wired his neutral safety switch and switched versions of software around the same time. I checked the version of software i sent him and it has the same rev limit as what he used to have. I have a feeling the different rev limit that different people with manual transmissions are seeing is a result of how they wire up their neutral safety switch and that you may in fact be hitting something else i think i saw in the software. I recall seeing something that looked like a speed limiter around 152 mph from the top of my head. I think you may be hitting that. I don't have a lot of time to spend on it now but my guess is the solution will be to figure out who has the best neutral safety switch wiring and everyone do theirs the same.

Earthworm 07-19-2005 12:44 PM

My system is wired like a factory 5MT. I know Jesse is missing a few switches.

I know I'm not hitting 152mph :) Highest I've gone is about 145 on the speedo.

I hit the same RPM wall regardless of speed. I have mentioned before that resetting the ECU gives me a couple hundred more RPM for a short while.

longassname 07-19-2005 12:59 PM

Quote:

Originally Posted by Earthworm
My system is wired like a factory 5MT. I know Jesse is missing a few switches.

I know I'm not hitting 152mph :) Highest I've gone is about 145 on the speedo.

I hit the same RPM wall regardless of speed. I have mentioned before that resetting the ECU gives me a couple hundred more RPM for a short while.

I'm not referring to your actual speed. I'm refering to how fast the ecu may think you are going based on rpm and the signals it is getting or not getting from the inhibitor switch. It may not be the speed limit but it warrants looking into. Of course 7000 on your tach may well be 7400 actual rpms or maybe you are right and when you get to the top of your mass air meter readings the engine just doesn't want to go anymore.

Earthworm 07-19-2005 01:14 PM

Probably the only way to determine this is by measuring the AFR on my car at the limits.

mbtoloczko 07-19-2005 02:28 PM

I used to think that the bucking was due the engine hitting redline and the tach not accurately reading the engine rpm, but yesterday, I say over 6500 rpm on the tach with no bucking. In my previous cold weather runs with the air density was higher, I'd be lucky if I got to 6500 before my car started bucking. I'm beginning to think more that the bucking is an artifact of the MAF reaching 4.8 volts. Either the engine is running lean and pulling back timing, or the ecu is cutting spark/fuel when it sees 4.8 volts from the MAF.

Chike, with the SVX, RA 3rd tops out at about 80-85 mph, and RA 4th tops out at about 100-105 mph with a 3.90 axle ratio.

svxsubaru1, If you want to run the stock fuel injectors with a turbo (or SC), you'll have to increase the baseline fuel pressure (unboosted fuel pressure). Otherwise, the injectors will reach maximum duty cycle (80%) at around 250 HP. 7 psi of boost would give close to 350 bhp. To supply enough fuel to the engine for 350 HP, you'll need to bump the baseline fuel pressure up to around 60 psi. Then at full boost, you're fuel pressure will be about 67 psi.

Michael, are you planning to include any sort of afr enrichment changes in the Stage 2v3 chip?

Chiketkd 07-19-2005 04:45 PM

Quote:

Originally Posted by longassname
That's about the same fuel pressure as with the walboro pump so it would be about the same--should work very well for forced induction. It might be a bit rich for a natrually aspirated car. You'll find the afr flattens out very nicely with the z32 meter and our software, richer in the lower rpms (decell is also improved). A naturally aspirated car should run the stock fuel pressure. A car with forced induction should run raised fuel pressure.

That's the thing Michael, with yor Stage 2v3 software, n/a cars can now achieve much higher hp numbers as their MAF won't be maxed out... (saw signs of my MAF maxing out during my dyno runs last winter when air was a cool 45* in the shop and my only 'power' mod was an STI panel filter).

With the stock fuel pressure and injectors, per Mychailo's post above, at max duty cycle 250hp is the most that can be achieved. I'd just want to be sure that your stage 2v3 software would be adaptable to changes an owner might make over the life of the vehicle (e.g. high powered n/a motor -> forced induction).

I've decided to keep my SVX indefinitely and not get an '05 Legacy GT just yet. However, I'd want to get the most performance out of an n/a EG33 without cracking open the block... ;)

-Chike

TomsSVX 07-19-2005 07:02 PM

Quote:

Originally Posted by Chiketkd

I've decided to keep my SVX indefinitely and not get an '05 Legacy GT just yet. However, I'd want to get the most performance out of an n/a EG33 without cracking open the block... ;)

-Chike

Glad to hear you are keeping it!! I guess since you don't leak oil anymore, the car is like new. Or at least looks it!!

Tom

Duckie 07-19-2005 07:34 PM

So after my stage III installed what will be left as far as options for me to suck more power out of this beast. Ideally I would hopefully get this heavy tub into the high 11's.

Chiketkd 07-19-2005 07:59 PM

Quote:

Originally Posted by tomssvx
Glad to hear you are keeping it!! I guess since you don't leak oil anymore, the car is like new. Or at least looks it!!

Tom

Yeah, but this car is frustrating to make faster. We'll see what the future holds. :) Even an '03+ WRX doesn't look bad at this point... ;)

-Chike

Chiketkd 07-19-2005 08:10 PM

Quote:

Originally Posted by Duckie
So after my stage III installed what will be left as far as options for me to suck more power out of this beast. Ideally I would hopefully get this heavy tub into the high 11's.

I'd see where you're at after the install. You might be in the high 12's...you might be in the low 13's (maybe higher depending on how heavy your car weighs). Getting to the 11's will take alot more horsepower than the stage 3 is going to provide. Maybe the 'built' low-compression piston Stage 4 motor LAN talks about doing in the future will get you even closer to the mark as you'll be able to run much higher boost than the 7-8psi he's running on his test car.

Going from high 12's/low 13's in a WRX/STI/Evo to the 11's typically takes and increase in those light-weight (3,200lb) cars of around 150+hp at the crank. If you don't believe me, read other boards like www.clubwrx.net or www.evolutionm.net.

-Chike

Duckie 07-19-2005 09:31 PM

Oh, trust me I believe you. I have a friend who is currently just above the 11 second mark in his evo.

And hell, I am only expecting a mid to high 13's from this kit. Why? I live in reno Nevada, mine is still a stock auto, ive got 16's on my car, and my driver's seat weighs 76 pounds.

I am just looking at options of where to go further after this. I will not stop modding this car tell I get kicked off the race track for not having a cage! And weight reduction is not an option unless its an exterior change (I.E make all of the outside carbon fiber) because I want this car to remain what it should be. A luxury sports sedanish type car.

Chiketkd 07-19-2005 09:55 PM

Quote:

Originally Posted by Duckie
I am just looking at options of where to go further after this. I will not stop modding this car tell I get kicked off the race track for not having a cage! And weight reduction is not an option unless its an exterior change (I.E make all of the outside carbon fiber) because I want this car to remain what it should be. A luxury sports sedanish type car.

Nice! Sounds like you have some solid plans for the car Duckie! Ever plan on driving cross-country to attend a Reading meet? If so, we should definitely meet up.

Once you get the Stage 3 in your car, if money wasn't an option, I'd buy a used low mileage 4.44 4EAT from a Legacy Outback and send it off for a Level 10 re-build including their valve body mod. Or go through the expense of doing a built 5MT or STI 6MT swap. The shorter gearing alone will improve your 1/4 mile time by over a 0.3 seconds...

The built stage 4 motor may then be the next way to go. You should be able to run 15 psi no problem as long as you have the right software from LAN to support it (which will then put you at roughly 450-460hp at the crank)!!! :eek: :cool:

-Chike

longassname 07-19-2005 10:25 PM

Quote:

Originally Posted by mbtoloczko
I used to think that the bucking was due the engine hitting redline and the tach not accurately reading the engine rpm, but yesterday, I say over 6500 rpm on the tach with no bucking. In my previous cold weather runs with the air density was higher, I'd be lucky if I got to 6500 before my car started bucking. I'm beginning to think more that the bucking is an artifact of the MAF reaching 4.8 volts. Either the engine is running lean and pulling back timing, or the ecu is cutting spark/fuel when it sees 4.8 volts from the MAF.

Chike, with the SVX, RA 3rd tops out at about 80-85 mph, and RA 4th tops out at about 100-105 mph with a 3.90 axle ratio.

svxsubaru1, If you want to run the stock fuel injectors with a turbo (or SC), you'll have to increase the baseline fuel pressure (unboosted fuel pressure). Otherwise, the injectors will reach maximum duty cycle (80%) at around 250 HP. 7 psi of boost would give close to 350 bhp. To supply enough fuel to the engine for 350 HP, you'll need to bump the baseline fuel pressure up to around 60 psi. Then at full boost, you're fuel pressure will be about 67 psi.

Michael, are you planning to include any sort of afr enrichment changes in the Stage 2v3 chip?

80% isn't max....100% is max and the max hp the fuel injector is capable of depends on the time available for fuel injection. The fuel injectors are capable of producing much more power than that at much lower fuel pressures. If you were in a situation where you were choosing fuel injectors then yes you would want to keep it under 80% for sure--in fact i would go with bigger injectors so i could direct a concentrated stream of fuel onto the valve easily for complete vaporization...this is what i did with stage 3 but when you are dealing with what you have it's a different story.

longassname 07-19-2005 10:38 PM

Quote:

Originally Posted by Chiketkd
That's the thing Michael, with yor Stage 2v3 software, n/a cars can now achieve much higher hp numbers as their MAF won't be maxed out... (saw signs of my MAF maxing out during my dyno runs last winter when air was a cool 45* in the shop and my only 'power' mod was an STI panel filter).

With the stock fuel pressure and injectors, per Mychailo's post above, at max duty cycle 250hp is the most that can be achieved. I'd just want to be sure that your stage 2v3 software would be adaptable to changes an owner might make over the life of the vehicle (e.g. high powered n/a motor -> forced induction).

I've decided to keep my SVX indefinitely and not get an '05 Legacy GT just yet. However, I'd want to get the most performance out of an n/a EG33 without cracking open the block... ;)

-Chike

Chike,

What can i say to that but ask which do you think is the better test of if you can get more out of the injectors a generic calculator or my having done it on our demo car? Theoretical speculation is great but you can't discard real data....you have to correct your assumptions or your reasoning when you find your speculation doesn't match the facts of what happens. Like i said to Mychailo 80% is 80% 100% is 100% Granted I'm getting a much better bsfc than a turbo system will but still no na svx will ever need larger injectors to run gasoline and if a turbo system needs more fuel it can get it through an additional injector controller which can supply fuel at high rpms but won't mess with the engine managment.

mbtoloczko 07-19-2005 11:29 PM

Quote:

Originally Posted by longassname
80% isn't max....100% is max and the max hp the fuel injector is capable of depends on the time available for fuel injection. The fuel injectors are capable of producing much more power than that at much lower fuel pressures...

100% may be the true max, but no one who tunes motors will recommend running anything over 85% duty cycle. I've seen flow rate vs fuel pressure curves from an SVX fuel injector, and I'd bet anything that its impossible to get 350 BHP from a boosted (SC or turbo) SVX motor running stock fuel injectors without running at least 60 psi line pressure. I'd say a more realistic number is a line pressure of 70 psi, and that may not be enough.


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