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on the hunt
32 Posts
Discussion Starter · #1 ·
Ok, I've tried searching first off to no avail.

question one: Is there any real difference between the 2.5sohc and the 2.2 sohc intake manifold?

question two: What year's/model's came with 2.2 dual port heads?

question three: I've gotten that the 2.2 heads don't flow as well but is this something that can be fixed with a decent port job and some delta regrinds?

Finally: What would be the best engine management for this combination? Can it be run off a stock ecu for a bit? And standalone is not an option.

Thanks for all the help. Motor is in pieces and I'm trying to decide if this is worth the time and effort to do.

Premium Member
overdeveloped beater
8,335 Posts
It depends on what design the EJ22 heads are. If they are phase I, they will have ribbed valvecovers that look like the EJ18 and need a phase I intake manifold. Phase II heads will look identical to the SOHC EJ25 except for the single exhaust port. Phase II heads will have the same intake manifold already, so they interchange.

It can be run off the stock ECU.

I don't think it's worth it to use the old dual port EJ22 heads. The valves are bigger on the phase II and the port shapes are better designed. EJ25 stuff fits in them so it's a better base to start off with. The only thing you have to change is the exhaust manifold.

Is it worth it? I think so, but that is subjective. I sold a phase II block to a guy in NC who built it up with phase II EJ22 heads and Delta cams. His 0-60 times dropped by 2 seconds. Well beyond RS territory and still OEM reliable.
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