Brainstorming an original EG33 turbo configuration

[SVXer95]

Sometimes I just don't understand the people on this board. You want it all! If you put in a large single turbo, you are going to lose bottom end. Period. Turbo cars act much differently. They generally don't have much power down low, then BAM turbo hits and you go like a bat out of hell.

You can't have the best of both worlds unless you want to build from scratch. Obviously nobody here wants to put the time or money into doing just that.

You want a really fast turbo SVX? Start with the block. CHANGE EVERYTHING ELSE.

If you want low end, go with an S/C. High end, go with a turbo. All around power and reliable, stay stock!

I am not trying to discourage anyone. I would love to see a turbo done right. (SVXtasy has his running, I wonder how it performs) BUT, to do it right and to satisfy you completely, you have to spend MONEY.

Silver:
I wasn't surprised you bought a car, just that you are importing it from the US. I would think that would cost more than the car.

[drivemusicnow]

Lets A) define a budget/cost that we could keep this under... just talking theory of what you should/could do is pretty worthless... lets put a price on it and say... what could we do with THIS much money...

You can't take the EG33 and make it the ultimate modified engine.. not enough money into R&D.. so lets look at some cost efficient ways to twin turbo or turbocharge the engine:

First, would there be a way to mount smaller turbos under/behind the motor, basically straight off each exhaust manifold? i don't know the clearence under there too well.. but i was thinking if so, you could run each turbo through a seperate small SMIC.
from the side mounts, two UICPs that run to the dual inlets in the intake manifold... (you'd probably want to have them meet and open together right before to eliminate differences between pressure, and allow a large blow through MAF to be placed there.

OH yeah.. that piping would be a nightmare. i wouldn't wish it on my worst enemy. However, plumbing work is cheap if you do it yourself, just takes time... and i'm guessing this would take you a VERY long while to work it all out. But it COULD be done, and it doesn't add a large cost to the progect.

obviously with a single turbo, you cut all this work in half (plus cut out a lot of harder ecu work and tuning too... )

Something that would be harder would be to fabricate all the neccesary flanges /exhaust manifold.. it maybe possible to adapt the stock manifold with some porting work, and do some creative adapting/welding to make it work.

If you tuned it correctly, and used a meth injection system(VERY IMPORTANT), you could probably keep the 10:1 compression ratio... the water/alchy would reduce temp and ability for knock/detonation. this setup wouldn't be ideal, but it could be done... (although looking into the ej22t pistons would be better) (are there performance aftermarket companies for the legacy turbo? they'd have the info you need.)
A complete stand alone ecu would probably be preferable to replace the stock, however if ECUTune (or someone else) could create a seperate "tuneable" application that would allow anyone and a laptop (with a cable and signal converter) to change the fuel map, timing, etc... (like the DSMlink for dsms) The tuning process could be handled. this would obviously be a farily large progect for anyone working on it.

Total cost would be over 5000$... probably closer to $8K with R&D costs with programming and such factored in. but it would be twin turbos, should be reliable, could probably hold more than 6 psi with the proper fuel modifications.

This can be done, as svxtasy has proven.. it'll take a while, and lots of headaches, but it can.. just be realistical in your plans/theories


Something that I was suprised with, is that you CAN run lots of boost on high compression.. .theres people runing 20 PSI on 10:1 compression pistons in dsms and makeing great power from it. The tuning process just must be more precise, and you can blow crap up MUCH more easily. and of course you'll break stuff... happens in every modified car... once you break it, you replace it with something stronger. (and much more expensive)

(please add other things that I dismissed that would be important to take into consideration, i didn't spend to much time on this, however i would like to spark a more realistic look at this)

[mbtoloczko]

Originally posted by UberRoo
...

* Two small turbos will spool up faster, allowing significantly improved throttle response.
* Having two turbos will allow them both to be placed very near the exhaust manifold, helping to keep them hot and effective.
* Having two turbos keeps the exhaust configuration simple, allowing the heat from the exhaust a very direct route somewhere else other than the engine compartment.
* Plumbing the intake is easier than plumbing the exhaust.

[/i]

Keep in mind that twin turbos may be smaller, but each turbo is getting half the amount of exhaust that a single turbo would get.

Not sure that I agree that plumbing would be easier. Two turbos means two intercoolers and all the plumbing needed for that.

From the perspective of tuning, building a twin turbo system seems more challenging. If both banks of cylinders are going to see the same boost response, then it will be necessary to make sure that the intake and turbo piping systems for the two turbos is indentical in flow characteristics.

[UberRoo]

Originally posted by mbtoloczko
Keep in mind that twin turbos may be smaller, but each turbo is getting half the amount of exhaust that a single turbo would get.

Not sure that I agree that plumbing would be easier. Two turbos means two intercoolers and all the plumbing needed for that.

From the perspective of tuning, building a twin turbo system seems more challenging. If both banks of cylinders are going to see the same boost response, then it will be necessary to make sure that the intake and turbo piping systems for the two turbos is identical in flow characteristics.

I pretty much agree with your perspective on simplicity. Performance was my primary consideration.

I do think that the plumbing on twins would be easier. The outlet of the compressor could go to a common collector and then be routed just as you'd route a single turbo with a single intercooler. Mounting the turbos in the front bumper as was suggested would be a royal pain. I envision a straight shot from the manifold to the turbines with the turbines' exhausts pointed towards each other and then bent backwards to join in a Y-pipe utilizing the factory exhaust. The compressor inlets would come in from the factory air filter, run down the back of the engine and into the compressor. The outlet would run forwards under the heads towards the front bumper and intercooler. Making the turbos fit in that space under and slightly behind the engine would be a bit tricky. (I haven't had a good look at it yet.) I think because the turbos would be fairly small, they'd fit with less difficulty. I have considered that modifying the main crossmember would be a possibly, but not absolutely necessary.

I agree that the two banks would probably not have identical flow characteristics, but that's actually pretty normal in any engine. Frequently the variation between cylinders on any engine is in excess of 15%. It's not ideal, but I don't see that as a problem.

SilverSpear, pistons are not accounted for. We have no idea what affects the compression ratio. A history of what ratios were used on which engines and when they changed would be a good indicator, but I don't happen to have that information.

[SilverSpear]

Originally posted by SVXer95

Silver:
I wasn't surprised you bought a car, just that you are importing it from the US. I would think that would cost more than the car.

I didn't say I am importing it from the US, I said that the car is next to my friend in FL, I am discussing with him the possibility of getting it to Lebanon. It will cost around $1000, but parting it over here will get me a lot more than the amnt spent. the SVX'ers over here are just waiting to c a wrecked SVX to be parted out. the doors only would sell for $1300.... once a guy brought one and sold it as parts. HE EVEN SOLD THE CHASSIS !!! the car was sold for a total of $4000.

[upnygimp]

Just FYI, there are some EG33 engines out there that are making quite a bit of HP. If you wanna build a monster EG33 you]re gonna be 100% on your own. There are companies out there that will make you all the parts you could possibly need, but bear in mind that you will be paying out the nose for them because they'll all have to be custom made for you. I have a feeling the EG33 has a lot of potential, it just needs to be unlocked by someone with deep, deep pockets.

[SilverSpear]

Originally posted by UberRoo


SilverSpear, pistons are not accounted for. We have no idea what affects the compression ratio. A history of what ratios were used on which engines and when they changed would be a good indicator, but I don't happen to have that information.

Ok let me put it this way, TUNING OVER HERE IS A LOT CHEAPER THAN IN THE STATES ! CAN SOMEBODY PLS TELL ME WHAT PARTS ARE INTERCHANGEABLE WITH OTHER SUBIES ! I know most of you are saying:"doesn't he get it this dumb *ssh*le ?" I am getting it allright the ECU and cams timing and everything, here we have experts for that, but I need to tell them which turbo parts we can use to upgrade the car.. in other words, the mechanical stuff not electronics !

I am up to it, but if you are not, I will do some research by myself.
I hope you got me now.

Man, this is all very good feedback. I really like hearing all the different takes on my ideas and suggestions.

As for using a single turbo I totally agree that this is the more cost effective and least hassle ridden way to go. I'm definately not made of money but I do have time on my side as I now have a spare complete EG33. I am not ruling anything out at this point.

The prospect of using the EJ22T psitons is one part I am going to look into. This is exactly one thing I was looking for. I have also been urged to go w/ a stand alone engine managment system by serveral people. I understand that this may be the most costly component in this set up but for reliability and efficiency, I understand that it is essential.

The purpose of this thread was not to declare the beginning of a massive and ignorant application of TT but to get some good "out of the box" thinking going on turbo applications. I'm very happy with the amount of responces to my thread and I appreciate everyones ideas and comments. I'm lucky to have so many great minds colaborating / debating on this concept.

Keep 'em coming!

Ok, while you COULD run high boost with 10:1 compression, the cost of running that motor would be ridiculous unless it was race only.

As far as things like 2 or 1 I/C and where it's mounted, probably isn't going to matter too much because it's not much boost and you don't want to create too much of a preasure drop by over doing it with the little turbos.

Too me, if you were going to do this. I would do the 5 or 6mt swap first, this will allow you to more easily get a stand alone, which willver allow you to closely monitor and adjust what's happening in the motor, knock, timing A/F ratios etc. Once you've got that, even though it may not be necessary, I would move or get rid of everything in the engine bay possible. It's just going to make plumbing easier and more efficient. Then I'd pick out two turbos, probable from something like a dsm, figure out where you can fit them and run piping.

It'd help to be good friends with someone who can use CAD well.

also going to be easier to use external wastegates I'd assume.

For sure this will be a couple year project, unless you start raking in some serious cash, but you do have the advantage of a spare motor, and access to good shop equipment.

Originally posted by UberRoo
The EG33 has a hemispherical chamber.

Where did you hear this? All evidence points to a pent-roof design, and wouldn't it be incredibly hard to have 4 valves in a hemi-head?

I think the EJ22T head is different than the EJ22 [N/A] head. The compression ratio difference may be in the head design, not the piston. I would think the cams and valves might be different at the very least, if not the entire head.

Yeah the EJ22T and EJ22E heads are different, the difference in compression ratio is in the pistons not the heads though. The cams and valves are also different.

Also, what are the compression ratios for all the motors in this discussion?

EJ22T - 8.0:1
EJ22E - 9.5:1
EG33D - 10.0:1

Did they ever change throughout the years? I seem to recall the EJ22 gained a few tenths on the ratio in the mid 90s, netting them a little more get-up-and-go. Perhaps this also happened with the EJ22T?

The EJ22E did get a lil more compression up to 9.7:1 in the later years, I think after 96 is when they started uping it. There were three different versions of it though. The orig one at 9.5:1 (non-interference), the next one at 9.7:1 (non-interference), and the last one at dunno what comp (interference). The EJ22T stayed the same 8.0:1 for all 4 years.

[i]If so, that would indicate that compression ratio is controlled by piston geometry, not head geometry. (That's good for you "just swap the piston" guys.)

Not quite. The second EJ22E had both a change to the head design and the piston design.

Originally posted by SilverSpear
in my opinion the EG33 shouldn't have a compression less than 9:1 , because driving at low rpm the SVX wouldn't have a lot of acceleration as it was especially because of its high weight. so a 9:1 compression ratio, the V1 chip and a nice turbo will do the trick.

I disagree, even the stock 8.0:1 on an EJ22T is quite driveable. Now add in two more cylinders and I doubt you'd even have to worry about it offboost.

Originally posted by Gt-Four195
Too me, if you were going to do this. I would do the 5 or 6mt swap first, this will allow you to more easily get a stand alone

what does the transmission have to do with the engine?

Originally posted by UberRoo
A history of what ratios were used on which engines and when they changed would be a good indicator, but I don't happen to have that information.

will this help?: http://wac.addr.com/auto/obs/turbo/ejcalcs.html

Sea, maybe you should try just doing the one turbo first just so you can get it all setup and whatnot, then go to two turbos if you so feel like it.

Also maybe you could try to mimic FHI's turbo exhaust design by having the manifolds facing foward and piping that comes from the Left manifold across the engine, joins the right manifold and goes over the crossmember under the head, which then flows to the turbo. You'd of course have to modify the crossmember to do this, but I'd be willing to bet if the control arms mount in the same area on the SVX as they do on the other new gen subarus you could use a turbo crossmember and not worry about reshaping the stock one.

[mbtoloczko]

Originally posted by THAWA


what does the transmission have to do with the engine?

The ECU and TCU talk to each other (torque control sent from TCU to the ECU, atmospheric pressure sensor output in the ECU sent to TCU, neutral switch and parking switch sent from TCU to ECU). With a 5/6 MT, those inputs/outputs can be ignored, so there is less time and hassle adapting an aftermarket ecu to an SVX with a 5MT.