EJ22T EJ20 hybrid to stroke or not to stroke + other advice

Heads, valves, pistons, rods, crankshaft, etc...

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k3rb3ros
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EJ22T EJ20 hybrid to stroke or not to stroke + other advice

Post by k3rb3ros »

I recently purchased a 1st gen Legacy SS to try my hand at the legendary EJ22T hybrid build. I am well aware that this no longer the best or most cost effective strategy to build a Subaru engine for power. But I have made up my mind to try my hand at doing this. The goal of this build is to build reliable and fun daily driver (runs on 91 pump gas) as in I can drive it conservatively every day and the engine won't fail for 3-5 years. I am thinking torque would be preferable to high rpm horsepower for daily driveability but I hear stroking the 2.2l puts extra side load on the pistons and causes the engine to fail sooner? Does anyone here have experience with this?

The question I can't seem to find enough information to definitively answer is should I stroke it to 2.35L or not? Both options I am considering will involve aftermarket forged pistons and rods most likely one of the kits from http://6starspeed.com/ejpeenrekit.html with some kind of EJ20 heads (ideally EJ20K or EJ20G heads so I can continue to use the Rob Tune 550 ECU the car came with). I've heard of people using heads from a 2.5L but the bore sizes are so different I worry this will require extra machining or cause reliability issues. Does anyone have experience with this? I am happy with rebuilding the engine in full but at this stage of the project I don't want to deal with rewiring the car to get it to (hopefully) work with some post OBD1 or standalone ECU unless I get suggested a really good reason (with a well documented and clear path to follow) as to why I should do this.

As for power output I am shooting for somewhere around 270-300whp as long as its fun and it doesn't blow up the tiny little 5 speed the car comes with. I am open to getting an STI 6 speed later but it's not in the budget right now. I am willing to build the engine to take massive boost later and tune it conservatively to operate in a range that feels sporty but that the transmission can handle.

As for the Turbo the car came with a VF-22 with an MBC, and 38mm Tial wastegate tuned to 17 PSI but it has compressor wheel damage and even if repaired I don't think it would be a very good turbo for daily driveability. I am thinking of downsizing to a VF-23 (as it would bolt right on to the exhaust exhaust setup and spool faster). I realize modern turbos are a lot better so if you have any convincing arguments about a specific set up that would be ideal for this use case I am open to suggestions. Keeping in mind that if I have to replace the up pipe and down pipe the gains better be worth the money.

I am looking forward to drawing from the knowledge of all the people here. I here this forum is full of shade tree ninjas when it comes to knowledge of building 1st gen legacy's.
k3rb3ros
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Re: EJ22T EJ20 hybrid to stroke or not to stroke + other adv

Post by k3rb3ros »

Also in case anyone else is reading this 6starspeed which is the first google result that comes up when you type QEJ22T rebuild kit" into google is no longer in business but their website is still active. Hopefully this will save some one else the trouble.
mike-tracy
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Re: EJ22T EJ20 hybrid to stroke or not to stroke + other adv

Post by mike-tracy »

I personally prefer the quick revving nature of the stock 75mm stroke engines, such as the ej20 and ej22's. If you've driven an ej25, either na or turbo, you'll see what I mean. Lumpier and slower. That'll be what a stroked ej22t will get you.

You can sleeve an ej22t out to 99-100mm bore, effectively creating your own closed deck ej25.
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote: Mon Jan 14, 2002 10:23 am Wait....I'm confused now.
k3rb3ros
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Re: EJ22T EJ20 hybrid to stroke or not to stroke + other adv

Post by k3rb3ros »

Do you have a daily driver built EJ22T?
mike-tracy
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Re: EJ22T EJ20 hybrid to stroke or not to stroke + other adv

Post by mike-tracy »

I do, yes. I'm currently using a vf23, but I had a td05 before. The vf23 doesn't have the same top end push, but the rediculous spool more than makes up for it. My old roommate has an 06 STI, and off boost both of our cars are about as responsive as the other.

I do have some ej20k heads in the garage waiting to be installed, because its obvious that the stock heads don't flow. But it's a trade-off, since the 22t heads (plus the short stroke) are why the car is so responsive down low. Dohc heads would shift the power delivery later down the RPMs.
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote: Mon Jan 14, 2002 10:23 am Wait....I'm confused now.
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