im looking into building up an NA EJ22E....

looking to get about 10.5 or 11 compression. Pistons/rings...Cobb spicey cams or equivilant.

I am wondering...what headgasket options do i have to increase compression AND 'power holding' capability?

Thanks for any help/advice in advance!

Im thinking of doing the same, so any info would be great.

you can deck the heads .020" each, use stock gaskets, and you should get around 10.5:1. you won't need to shim anything unless you get to .030" each head.

of course, WJM, using EJ18 heads would increase cr to about 11.5:1 and they use roller rockers as well.

But ej18 valves are so small, at least compared to RS valves.

But ej18 valves are so small, at least compared to RS valves.

Do you happen to know the size of ej18 valves? I wonder if their lack in size would nullify the benefits of raised compression.

-Lyle

some have said that the EJ18 and EJ22 are identical except for the dish in the combustion area is smaller on the EJ18. I don't know if this is true or not... I'll have a whole longblock running EJ18 to pick a part and disect in a matter of time.

Sounds like fun. I am just wondering if there would be any benefit to putting ej18 heads on a ej25. I guess it raises the compression a bit, although you would probaby loose out on some intake and exhaust flow.

The EJ18 and yhe older two port EJ2.2 have the same valves. EJ18 also has a roller cam.

the EJ25 would have MASSIVE compression, waaaay more than you could possibly make work with that combo. I could do the math, but it's pretty intense because the crank on an EJ25 moves the piston 2mm closer to the top of the block than the EJ18/20/22 crank, and has a ~100mm bore as opposed to ~88mm bore, so you see, a head designed to give a 75mm stroke, 88mm bore engine 9.5:1 CR would mean massive compression for a 79mm stroke 100mm bore engine.