I've alredy heard go EJ20 etc. but I wanna try something new..
Any comments would be awesome!
Upgrading from a EJ22...

EJ25 Phase 2 W/ DOHC heads..
Delta Cams
Port heads
TWE Super Stock Headers Coated
My Stromung Track Pipe + Cat-back will transfer too
Mr.Josh's Lightened Crank Pulley
255LPH Walbro Fuel Pump
TWE Valve Spring/Retainer kit
Injen CAI
Cometic Gasket

For the cometic gasket..it'd race the CR to like 11 or 12:1 wouldnt it? Would 12:1 be too much?
Any comments and advice would be nice.
-Eric

**This should all be done and in by mid sept at latest.

Sounds good. Nice list. I'd suggest that you research and see if you can find out wether or not you'll have interference with the cams and the thinner gasket.

And if you really want to try something different, Actually do it. There have been many threads of this nature started here only to die here with nothing ever really done. A couple have done some nice n/a builds. I can't remember their names.

Good luck.

I'll be paying attention to this thread as I'm getting a 2.5 dohc soon to replace my wimpy 1.8. It would be cool to find out if more than 165hp could be achievable reliably.

Sounds good. Nice list. I'd suggest that you research and see if you can find out wether or not you'll have interference with the cams and the thinner gasket.

And if you really want to try something different, Actually do it. There have been many threads of this nature started here only to die here with nothing ever really done. A couple have done some nice n/a builds. I can't remember their names.

Good luck.

Yeh i'm actually walkin the walk, I' just thought id post up and let sum guru's chime in w/ comments, I'm doin research more on the gasket / cam part but i think the final CR will be 11-12:1, i think 160whp is attainable easily w/ a tune.
I'll keep you guys posted :)
Thinkn about documenting w/ pictures as well who knows :)
-Eric
Any other comments are welcome!

Should be a nice NA build. Port match the intake manifold as well and make everything flow in smooth and out. A shot of Nitrous would give you some gains if you feel like laughing. Get those rods and lighten things some too!

the turbo route is always there if you're looking for MORE power. ;)

Don't be shy :)

You will already be at 10.8:1 by using a phase II block with the phase I DOHC heads on a stock head gasket. The DOHC heads are a few cc's smaller in combustion area than the SOHC ones. Make sure you do your calculations very carefully when you spec a thinner gasket.

You build seems to be lacking engine management. Without EM, 12:1 CR is nuts, and you won't see anywhere near to total potential power out of the engine. I currently make 138whp(uncorrected, at 5000ft, on a dynapack. I break 160whp on a Mustang dyno) with my set up at 11.5:1 CR, and figure another 15whp is to be found with tuning. And my heads aren't ported. Your goal of 160whp is totally feasible...

Hey Matt What about the difference between the SOHC and DOHC heads? Do you think there is much more to be gained by going with a DOHC head? I isn't the census that there really isn't that much of a difference to justify using them? Please enlighten me. :) InsaneAznKid if what i recall is right you should be able to save a good chunk of change.

Also since your upgrading your valve train and porting the head you might talk to Delta about doing a custom ground so you can take advantage of the amount of air you will be flowing with the heads from the port job. As a rule of thumb you should get the heads done first and see what there flowing and then give that info to delta and they should be able to come up with something that will complement the flow of the new heads.

You will already be at 10.8:1 by using a phase II block with the phase I DOHC heads on a stock head gasket. The DOHC heads are a few cc's smaller in combustion area than the SOHC ones. Make sure you do your calculations very carefully when you spec a thinner gasket.

You build seems to be lacking engine management. Without EM, 12:1 CR is nuts, and you won't see anywhere near to total potential power out of the engine. I currently make 138whp(uncorrected, at 5000ft, on a dynapack. I break 160whp on a Mustang dyno) with my set up at 11.5:1 CR, and figure another 15whp is to be found with tuning. And my heads aren't ported. Your goal of 160whp is totally feasible...

I will be getting EM in less than a yr after the engine is done and in, I wish I could have money falling from the skies or win the lottery :) Well anyways, we decided to ditch the cometic gaskets, not worth the hassle or troubles it can lead to. So i guess i'll just be at about 10.8:1 for CR.
u think 160whp is feasible w/out EM for a bit?
Also Matt, what is your build?
Thanks everyone!

let me address the sohc vs. dohc in reference to this build.

he has the dohc heads, got them for cheap. we were planning on going with a pI block, but from advice given on this board, decided to scrap that plan, and go with the pII short block. since the heads are useable for either, we decided to just go with these, run the stock bore on the pII block, and save money that way. the initial plan was to over-bore the pI block and go with custom pistons to raise displacement and bump compression. that was going to be a costly build.

the sohc heads are reportedly much better for a lower rpm torque monster. they flow similar numbers(search the n/a forum for some threads, the comparisons are there). the dohc heads tend to work better at higher rpm, with a small sacrifice down low. with the port work that is going into these heads, it should make up a good portion of that.

speaking of port work, here is the plan: the ports will be cleaned up and slightly contoured. all of the mating surfaces will be gasket matched. there will be no work done in the combustion chambers, and we'll be using stock sized valves.

a big thing to remember with these things is that the subaru heads, be them sohc, or dohc(for the 2.5L engines), ALL flow better then stock chevy lt1 heads. by a long shot(i'm pretty sure i read that in one of matt's posts.). any flow gains made in the head equate directly to hp, if you can use it.

this will be a fun buildup. your car's gonna be like night and day man.

--r

I gotchya, I did do i quick search and from what i read the DOHC heads aren't flowing too much more to make that much of a difference. And the only reason for the different types of power bands was more in the cam then anything else, but seeing as how a new cam is going in and the head is being ported the power band once again will be changed.

any flow gains made in the head equate directly to hp, if you can use it.

The reasons being that you should get heads done first and then get back to the cam manufacturer. My personal experience showed good usable gains of 11cfm at .300 lift which is a little less then stock lift, but some awesome gains at .500 lift 38cfm over stock, if this could be taken advantage of with the proper valvetrain setup i wouldn't be surprised of a 15hp gain to the wheels.

Cant wait to here about the output of the car.

I'm doing a similar, but different build. I think it'll be interesting to compare the results. I'm using a phase I EJ25, with higher compression pistons from a phase II EJ25. I opted for the sohc heads. I'll use the newer OEM 4-ply head gasket. Estimated compression ratio is about 11.4:1. I'm just starting the porting and polishing process. I had the cams done at Delta last week, and am looking into the Perfect Power engine management unit from Rallitech. A lightened, but not undersized, crank pulley, and Cobb equal length header, Bosal Brospeed 2.25 axle-back, oh yeah, and weird cold air intake that I made out of carbon fiber.

I'm doing a similar, but different build. I think it'll be interesting to compare the results. I'm using a phase I EJ25, with higher compression pistons from a phase II EJ25. I opted for the sohc heads. I'll use the newer OEM 4-ply head gasket. Estimated compression ratio is about 11.4:1. I'm just starting the porting and polishing process. I had the cams done at Delta last week, and am looking into the Perfect Power engine management unit from Rallitech. A lightened, but not undersized, crank pulley, and Cobb equal length header, Bosal Brospeed 2.25 axle-back, oh yeah, and weird cold air intake that I made out of carbon fiber.

You know when your build should be done and in? We should most definately compare results..as for delta..did you do a custom or did you just get a 'standard' regrind? I still have to send mine off and that's pretty much the last thing I have to do almost.

I'm just starting the porting and polishing, but finishing the engine isn't the big part of the job. It's going into my XT6, which currently has the stock ER27 in it. I'm changing the trans. (and rear end to a 4.44) As well as the complete wiring harnesses, but want to keep my air suspension and automatic seatbelts, so I have some electrical issues to figure out. The engine itself will be together in 3 - 4 days, but the swap will take a few weeks, as I have to leave it for a week in August to attend to some family matters out-of-province.
I got the standard 'mild street' grind'.

I've alredy heard go EJ20 etc. but I wanna try something new..
Any comments would be awesome!
Upgrading from a EJ22...

EJ25 Phase 2 W/ DOHC heads..
Delta Cams
Port heads
TWE Super Stock Headers Coated
My Stromung Track Pipe + Cat-back will transfer too
Mr.Josh's Lightened Crank Pulley
255LPH Walbro Fuel Pump
TWE Valve Spring/Retainer kit
Injen CAI
Cometic Gasket

For the cometic gasket..it'd race the CR to like 11 or 12:1 wouldnt it? Would 12:1 be too much?
Any comments and advice would be nice.
-Eric

**This should all be done and in by mid sept at latest.

Sounds great, Eric. I would like to see how things go, especially if you plan on raising compression. I'm also interested in P&P gains as well. Not that I'm going to do any of that myself, of course. Just living vicariously through you :lol:

Still, I don't know how you're able to resist going for a USDM EJ20T swap-- or, even cooler, a EJ22T! Your light little L would be so freakin' fast for the same amount of money. I still think it's cool to go the N/A route, though. It's definitely unique, but uniqueness comes at a price-- both cash and reliability.