EJ22T mod discussions for hardcores - you know who you are

[Larry Witherspoon]

BC-BF Legacy list members said I should post this here.

Seems like it revisits some of the stuff from just about exactly
one year ago

I Have a long term project to upgrade a spare EJ22T engine,
and I think you guys might like to bounce some engine design
opinions around

Plus there are QUESTIONS #1 AND #2

Even with the introduction of the STi, I still believe the EJ22T is
the strongest production block Subaru has ever made,
and would like to stay with it, although my modest desire to
double the 160 factory horsepower of the production engine
can be easily accommodated by the new age blocks out there now.

A while back I spent big bucks to have heads and valves from a
new Phase II 2001 RS 2.5 engine reworked and upgraded by
Dan Paramore

http://www.dprracing.com/ and ttp://www.dprracing2.com/home.html

Those heads are for sale, and anybody that wants pictures,
and what I call the full late nite TV infomercial about them,
send me email

ssspoon@aol.com

I decided against using them, mainly because of the lack of
some features not present on the 2.5 heads as on the stock
EJ22T heads.

Specifically, the EJ22T head coolant passages match the design
of the EJ22T block, and there are 3 holes in the right cylinder head
for the turbo oil supply, oil return, and coolant return

QUESTION #1
Anybody out there know if those features are present on the 2.0T or 2.5T turbo heads ?

Another concern I had about using the 2.5 heads on the 2.2T block
was the resulting compression ratio (C/R).

Increasing the 2.2 displacement is one of the considerations
for my project.

Have to go back and look at the references, but looks like some,
but not all 2.5 cranks will work nicely if I want to persue that option

QUESTION #2
What is the resulting C/R when a 2.5 crank is used in a 2.2T block,
and are new pistons necessary to prevent the EJ22T engine from
going from a non-interference to an interference condition ?

Also the 2.5 heads have larger intake valves, which may be desirable
for higher overall peak power and rpm potential, but my target
is low end street torque, and the smaller EJ22T valves may result
in higher intake flow at low RPM, and actually be more conducive
to the higher low end torque I seek, especially with the proper cam,
which might be the stock cam.

The factory REDUCED the size of the intake valves on the
2.2 turbo engine vs the 2.2 normally aspirated (N/A) engine.
Was that because the automotive engineers designing the EJ22T
engine to accommodate forced induction are stupid ?
I don't think so. The increase in torque produced by the turbo
version of the 2.2 engine over that of the 2.2 N/A version,
is significantly greater than the horsepower increase over that
of the 2.2 N/A version.

Although closely related, low speed performance,
AKA acceleration, is spelled TORQUE, not POWER.

To put things into perspective consider the following with special attention
to engine speeds

The 3.3 liter SVX was rated at
230 HP @ 5400 RPM and 228 Lbs-Ft of torque at 4400 RPM

The new 3.0 liter H-6 engines are rated at
212 HP @ 6000 RPM and 210 Lbs-Ft @ 4400 RPM

The 2.5 RS engine that my reworked heads are from, spec'd out at
165 HP @ 5600 RPM and 166 Lbs-Ft @ 4000 RPM

The North American WRX 2.0 engine is rated at 13.5 PSI max boost
227 HP @ 6000 RPM and 217 Lbs-Ft @ 4000 RPM

The impressive 2.5 STi factory numbers are given with 14.5 PSI max boost as
300 HP @ 6000 RPM and 300 Lbs-Ft @ 4000 RPM max boost 14.5 PSI

The original stock EJ22 engine provided
130 HP @ 5600 RPM and 137 Lbs-Ft at 4400 RPM

The figures for the lowly factory turbo EJ22T engine at 8.7 PSI max boost come in at
160 HP @ 5600 RPM, but check the torque...181 Lbs-Ft at only 2800 RPM

That's a 23% power increase and a 32% torque increase,
but the 32% torque increase is at a 36% lower engine speed.

The max torque comes at an engine speed that's less than two thirds
that of the normally aspirated engine. None of the other engines
have a torque band shifted to the left in the RPM range like the EJ22T.

And none of the other engines, turbo or N/A, produce torque figures greater than power figures

My desire is to expand the power and torque curves,
without shifting them, with engine balancing, increased boost,
enhanced ignition and induction controls, and perhaps
some lighter components.

Power and torque values with respect to boost are not exactly linear,
but if we just look for some ballpark ratio approximations for
reference points, and provide the EJ22T engine with as much boost
as the STi engine we get 267 HP and 302 Lbs-Ft.

That's without all the other improvements.

And there is something just plain appealing to me about working with
the type engine that originally came in the car without changing too
much unnecessarily. Especially if the gains achieved are at the
expense of headaches to get there, and more importantly,
if those changes bring a higher level of risk to reliability and durability
in the final result.

Somebody that want's fancy upgraded 2.5 Phase II heads,
please buy mine so I can have more money for hot rod work,
and you can save money on fancy upgraded 2.5 Phase II heads.

[rsstiboy]

take into consideration the different trim sizes for the turbos, yes you'll get earlier torque, but you'll also run out of puff before redline. the EJ22t has a tiny turbo for its displacement.

[Larry Witherspoon]

take into consideration the different trim sizes for the turbos, yes you'll get earlier torque, but you'll also run out of puff before redline. the EJ22t has a tiny turbo for its displacement.

Yes, thank you Rsstiboy

I have a brand new modified T25/T28 Garrett variable nozzle turbine (VNT) from Limit Engineering http://www.limitengineering.com/ waiting for me to ever finish this project.

Which reminds me, I need to go into the archives and see if there's somewho can switch out the older wheels for GT wheels. I have been told no, but I need to hear it from several sources.

[NuwanD]

I believe the USDM STI (2.5 turbo) is running a slightly higher compression ratio... 8.2:1

correct me if i'm wrong

[Larry Witherspoon]

Yes 8.2, but more than compression ratio USDM STi gets its' power from size and more boost than any other Soob - 14.5 PSI

The 2.0 liter 280 horsepower WRX engines still get more power per liter with less boost

[morgie]

I think the major factor for the EJ22t to have such a low torque is the turbo that come full boost at around 2600-2700rpm (may change now with the level of obstruction of the 10yld cat. )

have you looked at the numbers of the TT Legacy turbo engine ? They used a small and a big turbo to have great low-end torque, and even greater high-end torque

[Larry Witherspoon]

Hi Morgie - yes the small Turbo Legacy turbo probably contributes to the low end torque

The twin turbo owners seem to like going with a bigger turbo because of what i have heard described as the valley of death where the little turbo is out of breath and the big one is not yet up to speed.

My approach to the problem is to use a turbo with a variable turbine nozzile that acts like a small turbo at low engine speeds, then opens up to handle more volume at higher speeds --- no lag and still breathing at top end

Larry

[THAWA]

or what about using a slightly larger turbo for the lower rpms and a slightly smaller turbo for the higher rpms?

[morgie]

As for the Question #2 answer, i don't think you can simply swap the crank, bolt all up and run like that.

with the 75mm stroke the pistons gets higher than the deck at TOP-dead position. With 79mm, the piston might not even clear the head.

AxisPowersomething did this convertion. They first had to relocate the wrist pin higer on the piston. This results in the piston going lower at bottom-dead-position, and interfer with the oil sprinkler. So you also have to shorten the piston, or at least modify it.

[Larry Witherspoon]

Yeah Morgie see that's over the top for me

That's fine for somebody out to set a new class record but I'm not ready for something so rad to drive back and forth to work you know where I'm comming from ?

Good to know though, thank you very much

Larry ssspoon

[rsstiboy]

if you can run some extractors, run each bank into the new VF37 twin scroll twin entry twin wastegate STi turbo, you'll get fantastic response down low without sacrificing top end, it will be good for a 2.2 motor.

[Matt Monson]

Larry,
Here is my planned build:
EJ22T block with stock crank and rods. Custom forged pistons to bump the CR to 9.0:1 for use with EJ20K heads (bone stock, no upgrades to the heads). I have not checked the coolant passages, but several reputible people have told me it is a non-issue.
I am using a VF-28 turbo. It fully spools by 2900rpm and makes around 17psi @7000rpm redline.
The CR will aid in off boost driveability and consistent performance. I have run the numbers and expect it to be around 350CHP and a bit more than that on the torque side. And it should have a big fat flat torque curve.

I am a firm believer in OEM parts and don't find the need to over-do for bling factor. The only non-OEM part that will be used in this build is the pistons...

[morgie]

same here except I also change rods

i think the 2.2l displacement will be enought to produce good HP, and 2.33l upgrade will cost more to make.. may allow some little Hp more, but you could also get those HP numbers with some little upgrades on the 2.2l

[aspect]

where can you get forged or otherwise strengthened (titanium? =D) rods for the 2.2?

[morgie]

any rods designed for the WRX will fit.

They share the same specs. I got mine from Eagle Rods.

[greg donovan]

where can you get forged or otherwise strengthened (titanium? =D) rods for the 2.2?

this site has alot of stuff:
http://www.importperformanceparts.net/i ... ubaru.html

i personally havent dealt with them. but the selection looks good.