Can anyone with experience with these motors give me a ballpark of what I can expect without changing pistons? Iv got a DC header Apex-i w.s. exhaust and cold air intake, crower stage 4 cams on the way with Apex-i Afc.

 

142 stock + I/H/E 163 hp around and the cams 180 hp tuned....... I say about 145 to 150 at the wheels.

your compression has to be bumped for the cams to really shine.

If I were you I would get a skunk2 manifold and some ctr pistons.

my 2 cents good luck, mang

 

I hope that You are also getting the appropriate valvetrain upgrades, i.e. dual valve springs and better retainers. Those stage 4 cams with no additional top or bottom end work are going to shift your powerband up very high. I think those cams peak power at around 8200 rpms. I would not want to rev a non-built b18b to any more than 7500 rpms. You can't expect to just throw some high lift cams into the mix and expect to make power.

 

I've done the research for a local. I agree, you gotta swap out those pistons and bump the compression. Don't want to have too big of a cam on stock compression, you'll overcam your engine. I'd say aim for about a 11:1 CR. Did the math and I think that got some of the best results. :]

 

If this is true, you need to compliment those cams with high comp pistons. I would suggest 12:1 pistons, and some good tuning like hondata and a nice tuner.