ok need your guys opinions which is better if any the sti ej20k (version 3) or the wrx ej20k (version 3) to build a 400 to 500 hp monster

Isn't the STI a WRX? It is just tuned BY STI?


RawCode

Well, STI Engine is already tuned for more power by the Tuner.
The internals are beefed up to take more boost. The Turbo itself is larger too.
Naturally WRX STi makes more power than stock WRX.
Therefore you should be able to squize more power form a STI .

RawCode: Think of it this way. WRX STI to WRX is like SVT Mustang to Mustang GT.

STi is a in-house tuner who relases their own versions of the car.

That's my 2 cents.

Both engines make the same horsepower stock (280), but I'd assume the feel and the tunability is different.

I'd definitely go for STi motor, but since you are trying to make 400 -500 horse power, I think you'll need to change internals anyways(JUN stuffs etc.) , then WRX motor will be cheeper.

Well I knew that much ! lol :lol:

My thought was, if your gonna build up an ej20 engine for 400-500 hp, you will be doing a lot of work on both engines no matter what. Why not start with the normal wrx block and do it your way?

OR does the STI block have different cooling and oiling passages, and other advantages like a closed deck and such. I have not read much about the sti engines as I haven't needed to as of yet! :p

RawCode

If you're going to attempt to get 500bhp, or even 400bhp out of the EJ20, don't wast your time or money on buying either engine.

Start off with one of the early EJ20 closed deck blocks, and build from there. I'd also get hold of some STi heads, and matching inlet manifold, either version 3/4, or 5/6, depending on what MY will make life easier to fit your current car.

You can forget using any of the VF turbo's, they're just not big enough, and apart from the STi having forged pistons, the internals are the same. Even these I would ditch.

A 2.lt with 500bhp, will be VERY hard to achieve, and if you do, it will be totally impractical as a daily driver. Hope you know what you're letting yourself in for :lol:

Happy.

Originally posted by Happy
If you're going to attempt to get 500bhp, or even 400bhp out of the EJ20, don't wast your time or money on buying either engine.

Start off with one of the early EJ20 closed deck blocks, and build from there. I'd also get hold of some STi heads, and matching inlet manifold, either version 3/4, or 5/6, depending on what MY will make life easier to fit your current car.

You can forget using any of the VF turbo's, they're just not big enough, and apart from the STi having forged pistons, the internals are the same. Even these I would ditch.

A 2.lt with 500bhp, will be VERY hard to achieve, and if you do, it will be totally impractical as a daily driver. Hope you know what you're letting yourself in for :lol:

Happy.

thank you happy, you said everything that needed to be....EJ20 w/ 500 HP=no power till 6k RPM when it finally hits boost.

jeremy

Happy is right about the closed deck block (RA) being the one to build. He is also right about the car being unstreetable for the most part.

If you went for +-325 HP it would be more practical for a daily driver, although
any 2.0L turbo motor with that much juice wil still be pretty pipey around town.

Besides forged pistons the STi motor also has a better valvetrain that allows the engine to redline at 8250. This means shorter overall gearing and better acceleration. I think you could probably get 400hp with a stroker kit and that would probably be the upper streetability limit.

-Michael