Hybrid motor question

[Sarra]

Since I'm too tired (read, lazy) to actually look, what is the resulting compression ratio from combining a 2.2 liter block with EJ25D heads?

For forced induction, other than the factory turboed 2.2 liter blocks, which are the best for boost? I'm assuming twin port, so I can use either stock exhaust, or something similar to stock (like an OBX with a custom made section for the Cat).

I'm more interested in learning more about the specifics, like, can I use stock injectors, ECU, and accessories, or will I have to find a standalone setup?

I need to keep ODBII and I&M conformant, so I can't stick a 1990's turbo motor in there and pass inspection. =\ Are there any EM options I can use that would let me keep this car ODBII compliant?

Anything else about doing a hybrid block/heads build? Alternatives blocks, like an EJ205? I'm looking for inexpensive, but I don't want to cheap out. I could always just stick one of those tornado things on there... But, I want something that's actually faster!

[AJM]

Ej25 dohc heads+ej22 block=8:5 or somewhere close to around there. To build this hybrid you must turbo it.

How about ej20 dohc heads with ej22 block...


Or for high compression n/a ej22 block with ej18 heads.

Ethier way probably phase one parts are best, not only are they non interference, but have stronger internals.


You can use the stock ecu ,but piggy backs will be needed. rising rate fuel controller, boost control, etc. Of course another way to control boost is exhaust diameter ,ect.

FOR THE LOVE OF GOD AND ALL THAT IS HOLY DO NOT USE STOCK INJECTORS! They only run around 270cc (edit:ej22 injector #'s), not nearly enough for any type of forced induction. Consdier at least wrx injectors or rails (this will convert to top feed if you don't already have top feeds), even better perrin rails and sti injectors (good old side feed). Of course you'll also need a better fuel pump ,and walbros can be had rather cheaply any more. (under $120)

Any Subaru n/a motor with stock internals will probably only run around 7 psi max safely. 5 is safe, 4 psi is super safe. When I finally get the money to finish my turbo prodject i'll be shooting for 4-5...

[Wiscon_Mark]

Douglas Vincent is running about 13-15 PSI on his crazy EJ22E motor :lol:

[Sarra]

Plan would be to get an EJ22E block, put my EJ25D heads on, throw on some high flow injectors and either WRX or STi rails, and... What kind of piggyback for EM? I'm sure a SAFC won't work.

And, there won't be any using the exhaust to control boost, but I'll get to that when I get an EJ22E block. I want to prepare for what kind of EM is available.

If I go turbo, I'll grab WRX front and rear X members.

Actually, my question was more along the lines of "what about an EJ20 block with EJ25D heads"? I wouldn't use EJ22 heads (unless we're talking turbo heads).

Basically, I don't want to pull my motor, throw the heads on a new block, plop it back in, then realize I need something else to get it running. I'm kinda tempted to buy a bunch of parts and just take the car to PDX tuning...

EJ25D heads
EJ22E block
STi fuel rails and injectors
Some kind of EM
X Members
New stock clutch

Brakes will be upgraded by then. Suspension mods will follow, once I make my mind up on if I'm gonna swap the rear X member as well, or not.

[Sarra]

Also something I want to ask. Will changing the block require a different exhaust setup? Or will the exhaust ports remain in the same area, in relation to the rest of the car?

[Huffer]

Exhaust location the same, unless you go turbo...

[Sarra]

Exhaust location the same, unless you go turbo...

Nope, going for teh electric supercharger (AKA, I'm gonna hook an Eaton M62 up to a 12 hp lawnmower engine), so stock exhaust should be sufficient.