Hello guys,
I would like to have some light into a project I dare to start a few days ago, however, I'll appreciate a lot if somebody could have some useful info about this topic.
Well, I am working in a EJ20E JDM NA engine rebuild. I have in hand both complete EJ22E NA USDM heads and I am thinking to use them in this engine, in order to get more power and performance. When comparing all heads side by side, here what I got from a visual inspection:
1) Valve base have different diameter. For EJ20E intake valves are 32 mm and exhaust are 28, while EJ22E intake valves are 36 and exhaust 32 mm.
2) They look very similar. Same holes, external size, water and oil channels, same bolts holes location and position.
3) I can't see any difference between camshafts, however, they could have a different valve lifting time, but I don't have proper tools to measure this.
4) EJ20E is SOHC, exactly the same than EJ22E. The first one brings 92 mm pistons, while EJ22E is about 97 mm. So, first one only delivers 116 HP, compared with 135 HP delivered by EJ22E.
5) EJ20E has a slightly lower compression chamber, what is not noticeable in a simple view. This is for sure due to it uses smaller pistons. All heads have a twin chamber in exhaust ports with 3 bolts, so they look exactly the same.
My question is: do you consider I could have a loss of power if I use these EJ22E heads in an EJ20E block? Does anybody have more useful info that could give me more technical specs or useful tips in order to have more performance of this engine?
P.D.: I am porting and polishing these EJ22E heads...
Thank you for your comments!
Elver.