Info on my turbo engine build up

[ciper]

In researching JE Pistons I found a page with some useful specs.
http://www.jepistons.com/pdf/2002-sport ... subaru.pdf

Using that I can calculate the CR for my engine if I was to use the SOHC heads and the JE SOHC stock size pistons

bore 99.5mm stroke 75mm head 51cc piston 24.5cc gasket .062mm Calculated C/R 8.68:1

To double check that number I tried the stock specs for an EJ25
bore 99.5mm stroke 79mm head 51cc piston 24.5cc gasket .062mm Calculated C/R 9.09:1

They list 8.5:1 on the site.

Now Im really confused. How the hell am I getting diffferent numbers?

[Larry Witherspoon]

Ciper is struggling with head numbers and configurations, as do we all once we start doing head research. Next will be headers, just watch.
Ciper please say you will use the stock turbo heads or DOHC heads or 350 Chevy heads or anything but SOHC heads. If as you say "The price for performance calculation shows that my money would be better spent on the pistons and head modifications if I had extra." And "Thanks to Matt Monson and the information I found SOHC heads are now the current route." Ciper if you say those things, try as I might to resist, I am uncontrollably compelled to offer a shameless plug for my advertisement. Check the Parts Shed for subject "Upgraded 2001 Phase II Heads". Meantime, instead of trying to figure out what heads can do what and give what, maybe try the approach of deciding what you want out of the engine. If you just say "I want max horsepower and the most efficient heads on the planet", then you want a pro drag racing engine or Bonneville engine, with $7000 heads, no compromise, no bottom end torque, no reliability, no nothing but peak HP at 10 grand RPM for one weekend then it needs a teardown and rebuild. But seems like you are starting to place some limits and set some targets out there. So now we can look at the available heads and see what potential they have for you. If you're leaning towards top end, that points to some heads over others. Bottom end, points in a different direction. Happy medium compromise equals more choices. But hey, I should talk. I get something into my head as the just right combo, and it's hard to quit. I guess the best advice I can offer is, unless you're after a class record where every little bit can mean the difference, you won't notice the few horsepower difference an optimum combo has over one that's only very good.

[Matt Monson]

Larry,
As is generally the case, your post is pretty dead on. I run into my fickleness as I progress on my own build ideas, but I will share my build plans as they currently stand. I am looking for a sleeper Legacy with quick spool and plenty of low umph. 325-350hp should be the ballpark, but as others have said before, the point is to build and tune it right and the horsepower will be within a forseeable range. If you have your heart dead set on a HP number, it is harder to hit and tune in my eyes.

So, the plan is as follows:

EJ22 block using the spare EJ257 pistons that will be left over after my RS build (I am using the shortblock on an NA build with 12:1 pistons, but that is another story).

Stage II SOHC EJ25 heads. Stock, except for TWE springs and retainers. I think the stronger springs should be in there not for the revs(which will go to 7000rpm) but more for the boost. High boost can cause valve float.

VF-28 turbo. This is virtually identical to the VF-24. It is a good turbo for auto cars. Max psi is about 18psi at 7000rpm. This is the same turbo used on 300hp v6STi's. I think it should flow enough to hit my hp goals on the slightly bigger engine. If not, I am not to attached to the actual #'s

STi v6 intake manifold/TB and 480 cc injectors. This and a fuel pump should ensure enough fuel to my reckoning.

Of course things could always change. My GF might bet STi heads on her '04 WRX by the time I am building and I might just grab her stock heads. The cores on the USDM EJ205's are identical to JDM v5 and v6 STi's.

Ciper,
To answer your specific ques:
1. I think the JE pistons are a custom job at 8.5:1CR As mentioned they are 100mm and for an RS-T
2. IIRC the EJ257 pistons are 8:1 CR. Regardless, I am using them because they are in essence free and new and quality.

3.Mark Rameriz pointed out in one of his posts that changing which head gasket cam move you around in your CR a good deal. I will find something that works for my goal of low 8's. TWE's solution is interesting, but not new. Folks have been stacking gaskets for years. I chat with Keith at TWE quite a bit. They will likely be helping me work out those finer details when it happens. They also might influence my choice of heads and whatnot. I have been asked to not share details, but as they told you, they are doing some racing EJ22 builds that may have some trickle down to duffers like us.

So, my question is...Is it bad form to have a Cobb built AND a TWE built Subaru in the same garage?

[ciper]

Larry Witherspoon: I got slightly burned back in my Supra days because I didnt know what the hell I wanted.

Ive written so many messages on this topic I cant remember where I have said what. I have done exactly what you suggest "deciding what you want out of the engine."
Thats how Im getting to these questions, Ive seen some wild stuff available and turned it down because it doesnt fit my needs.

The happy medium is where Im headed. My peak HP goal is for 250-325. More important to me is a good power curve througout.
Too many people would say to turn the boost up to 20 psi and I could get that on a stock engine, no thanks! I plan to do this once and do it right. I want to build the engine that will go another 200k miles just like one directly from subaru.

Ill check your for sale ad.


Matt Monson: Your build ideas are getting to be very similar to mine.
One thing, the math I did was for the STOCK sized piston as mentioned on the site, so it should work properly.

The ones you mention, do you know the dish volume? I could try and calculate it as well.

About stacking gaskets, Ive never heard of dissasembling multiple gaskets and then using the left over bits as a combination of "shims"

TWE may have shared the same information with me.
What kind of price did you get on the valve springs and retainers?

[Matt Monson]

I haven't picked up the springs yet. Cash flow is a little tight right now with Cobb headers hitting my card next week I won't be doing any of the major work on the Legacy until March or April when the RS is back together and road worthy...

[Larry Witherspoon]

Wish I were as far along as you guys
I'm still collecting parts
Sounds like we're on different stages of the same trail
My philosophy for a good street turbo engine

First build the engine;

1) Balance and blueprint - good clearances, low friction, smooth

2) Stronger lighter components - more HP and torque, less effort

3) Get the heads breathing as well as practical - heck try to clean up the whole induction system from intake to exhaust

Now, you have more reliability and a lot more power without even touching the boost.

4) If you can make the mental transition to handle the money for a stand alone engine management system, it can provide the same kind of power per dollar as the stuff in 1, 2, and 3

5) Now with all the above improvements you can increase the boost much less than you would have to with the stock engine to get the same kind of power and torque, but without all the additional stress and heat, or you can increase it the same amount, get much more power, and be better equipped to handle the additional stress and heat

Don't worry about power, it will come onto thee

Oh I almost forgot 6) which may actually be 1 or 2 or 3...reworked trans can add a surprising boost to performance...and may be necessary to realize the extra power you now have....not cheap

None of this is cheap and you're both nuts to fool around with a perfectly good car in the first place. Your place in heaven would be guaranteed if you took all the money you're foolishly spending and donated it to The Sisters of Perpetual Mercy for Wayward Girls

[Matt Monson]

Me,
I am absolutely certifiable. Who but an insane man would spend close to $10K on an engine to drop into a $10K car? (that is the RS build). But then when I am done, I may very well have the most powerful all motor street driven RS in the country.(Do not quote me on that, I said "may", not "will" )

And as for the Legacy...well I bought it because I went back and forth on turbo vs. NA for so long with the RS that I just had to do both! It was the cheapest and most unique route with Subaru's strongest block ever...

As for the other remarks. Yes, I will be getting stand alone management. And I also hope to do one of the first(if not the first) 5EAT w/paddle shifter swaps into a BF. But that is still quite a ways off. Fortunately I am a very patient man...

[ciper]

Larry Witherspoon:

1. Since the engine was turbo to begin with do you think much (if any) work needs to be done on the lower end (other than piston choice). It seems to me that most of the focus would be on the head and parts contained within (cam profile for example)

2. Stronger components are definatly needed, though I feel that some of the components of the EJ22t are already at the strength level needed. One weak point I plan to address is the head sealing, ARP Head studs and machine work will be my plan.

3. I agree.

4. I agree with this as well. With the correct tuning it can end up being cheaper than any other additional modification

5. Exactly. Thats why I plan to run the car at stock boost levels until everything else has been completed. I want my car to be complete and look for any bugs before changing anything. If you change too much at one time it makes troubleshooting VERY hard.

Your right that its crazy to spend this much money. The value of my car is already well below the cost. Adding this engine makes it so negative its not even funny. My argument to this is I dont judge the car by everyone elses value, rather my own internal value says this is the right thing to do.

[vrg3]

One quick point -- it is possible to make the factory engine management perform at levels on par with what you'd get with aftermarket management. It just takes some work to crack it.

I agree with everything you guys are saying... just wanted to pick a nit. :)

[Larry Witherspoon]

Ciper wrote

Q:
1. Since the engine was turbo to begin with do you think much (if any) work needs to be done on the lower end (other than piston choice). It seems to me that most of the focus would be on the head and parts contained within (cam profile for example)

A:
Posolutely correct. The EJ22T is the mother of all Subaru bottom ends. It will easily handle the power target you are anticipating. I believe guys who go with aftermarket components there are usually after lighter weight for higher rpm potential and throttle response, unless they're planning on insane boost, then maybe pistons would be in order

Q:
2. Stronger components are definatly needed, though I feel that some of the components of the EJ22t are already at the strength level needed. One weak point I plan to address is the head sealing, ARP Head studs and machine work will be my plan.

A:
Also maybe look into copper gaskets and "O-ringing" the deck. But probably not necessary if you are not planning on boosting past the low psi our pump gas will support, like in the 20 psi range

Q:
Your right that its crazy to spend this much money. The value of my car is already well below the cost. Adding this engine makes it so negative its not even funny. My argument to this is I dont judge the car by everyone elses value, rather my own internal value says this is the right thing to do.

A:
That's a pretty good answer. I'll have to try and remember that one when I start feeling guilty about my hot rods cost. Though I have to say I was kind of dissappointed when neither you or Matt rose to take the bait and ask where you could send money for the Sisters. Guess I'll have to work on my sermon.

and VRG3 wrote;
One quick point -- it is possible to make the factory engine management perform at levels on par with what you'd get with aftermarket management. It just takes some work to crack it.

VRG that is quite a revelation. I would be surprised if the factory ECU could be made to provide optimum air fuel ratio 3D mapping across a wide range of changing RPM, load, and other conditions. Could you maybe point us at somebody doing this kind of work? I am aware of Alan Croxford at IWTU Electronics http://www.iwtuelectronics.com/ but not sure if he is able to provide the kind of control of a stand alone EMS. Can anybody else out there add more to what VRG says?

[vrg3]

What aftermarket ECU provides 3D mapping? All the ones I've seen are 2D, like the stock ones.

My understanding was that the strength of aftermarket engine management was just that you could specify arbitrary maps. If you figure out how to remap the stock ECU, you can get that same advantage.

I personally am trying to hack the stock Legacy Turbo ECU (see the thread in the Engine forum called "Have I found the ECU's maps?" or something similar)... I do believe I have figured out how to remap a 1992 non-turbo ECU that I have, but the fuel map in the turbo ECU still evades me.

[Legacy777]

Hey Larry, just want to throw a comment about your comment

A:
Also maybe look into copper gaskets and "O-ringing" the deck. But probably not necessary if you are not planning on boosting past the low psi our pump gas will support, like in the 20 psi range

Rod was looking at copper HG's, but after doing some more homework, he found that for a street driven application, they're not too pratical since they need frequent re-torquing.

I do have do have another question/comment about your O-ringing the deck. It was my understanding this was done on open deck motors to help 'secure' the cylinder portion of the block and keep them from moving around at high boost. On a closed block motor....I don't see the benefit, unless of course there are supposed other benefits from O-ringing.

[morgie]

humm, my brain is boiling after that 3 page read..

I'll digest that and ask some questions later.

[ciper]

Regarding 2.5 heads and some of the issues,

"BORE differences." This is not a problem. Already the 2.5 heads have a large Quench area that actually extends into the bore area. Meaning if your head gasket is too thin the pistons will strike the head. The smaller bore of the turbo will reduce this area, causing a less optimal setup but a step is not a problem.

"Headers" So we all know that the dual port exhaust 2.2 NA heads can use the 2.5 dual port headers right? Well the 2.2 Turbo headers will bolt up to a 2.2NA head? So:
2.2Turbo Head = 2.0Turbo Head
2.2NA DP Head = 2.2Turbo Head
2.2NA DP Head = 2.5NA Head
Which means that
2.2Turbo Head = 2.5NA head
2.0Turbo Head = 2.5NA head

Right? Did I get something wrong, the whole equation depends on 2.2NA heads being the same as 2.2Turbo heads

Can anyone confirm the 2.2NA to 2.2Turbo head interchange?

[Matt Monson]

Legos...

[ciper]

Be quiet you!

[morgie]

Legos...

hehe that's what i always say to friends


Ciper : or you could remove the 2.2na = 2.5na part of your equation, and replace it by 2.0t = 2.5na or 2.2t = 2.5na directly

for sure the flanges are the same. But is the flange-to-flange distance the same ? Can this info be found in the shop manuals ? if so, i could go check this out this evening.

[morgie]

after my tests this evening (see engine section).

Ej22t = sohc
ej20t = dohc

ej22t intake != ej20T intake

BUT

ej22t exaust == ej20t exaust (we can use Wrx exaust on our ej22t)

so, we could say
sohc intake != dohc intake
but
sohc exaust == dohc exaust

to be verified, but i hope this helps a little

[ciper]

Just to add more info, it looks like the difference between a California emissions car and a 49 state is only a ground on the vehicle wire harness.

So if you swap an ECU from a federal car into a California car the ECU will start to report California emissions.

This is important because of something posted here
http://bbs.legacycentral.org/viewtopic.php?t=14441


http://www.smogcheck.ca.gov/StdPage.asp ... n_1994.htm
California Certification
A federal Environmental Protection Agency (EPA) certified (federal or 49-state) engine cannot be used in a vehicle that was originally certified for California.



This also means you can enable California emissions reporting (and who knows what else it changes in the ECU) by grounding the pin manually. If its found that the California pin reduces performance in some way I will most likely remove this connection, except for smog tests.

[Brat4by4]

Maybe be VRG3 can do a dump of the turbo ecu with the pin grounded and one without and compare them. or maybe the NA ecu since he can read it better. you know you wanna vr....

[Legacy777]

Maybe be VRG3 can do a dump of the turbo ecu with the pin grounded and one without and compare them. or maybe the NA ecu since he can read it better. you know you wanna vr....

That would actually be pretty cool to see if cali cars do things differently....

[vrg3]

I would be happy to try anything out for you guys, but this request doesn't actually make any sense.

The ECU dumps I've been playing with are dumps of the read-only-memory built into the ECU. Changing the values of inputs has absolutely no effect on them. I can even pull the ROM chip out of the ECU and read the complete dump directly off the chip outside the ECU.

Now... if I can ever wrap my head around all the code that I've disassembled from the dumps, then I could tell you for sure what the difference in behavior is. But that's hard to do. So give me time. :)

[vrg3]

Hmm... so I scoured through the disassembled code...

There do appear to be places where the ECU checks which jurisdiction it's in and uses different lookup tables depending on the answer. In at least one case on my ECU, both the California and Federal/Canada tables are identical. That is all I can say for the moment; I don't know what these lookup tables are for or anything like that yet.

[ciper]

I realized something today.

Lets say I spend 850 for a set of heads with aftermarket cams (someone PM'd me with a good deal)
Add 700$ to get it working for example intake, coolant/oil, electronics etc. 700 was a price that Nate from S-Squared and I guessed up from some very long discussions that Ill compress and post later.

Now thats 1850 and alot of custom stuff. I still like the idea of SOHC
BUT

What If I took the stock EJ22T heads and spent 1850 on them? They would obviously be 100% plug and play, no custom work needed. For 1800 dollars I could get some serious stuff done to them.

I hope you guys dont hate me for not being adventurios/unique. Already Im going to spend over 5000$ just to get a stock EJ22T installed in the car. Sure it will be better than a brand new EJ22T from the factory and ready lots of power later but! I wouldnt doubt the engine only makes 170Hp and 185 torque to start, not a very good performance for dollar upgrade.

It seems that my project is slowly morphing into building a rock solid EJ22 the build power on it.

If I do plan to go this route I now need help on deciding what to do with the EJ22T heads.

Are there any cams available, possibly from another SOHC subaru that would fit?

What head mofications would result in maximum reliability and performance for the money?

Your next question is probably going to be about my goals.
1. It has to be able to run on the stock engine/exhaust/engine management for a while
2. It has to pass a smog inspection (should be easy especially from what Ive seen on WRX)
3. Estimated power will be above 300.


About the engine, think of any part that would ever wear out and I have already replaced it with something equal to or better than factory. It will be completely torn down and reassembled from scratch.

[Legacy777]

Just stick with the stock heads, get them worked over, and get some custom cams.....that way you can take care of all your bases