Thread: Help with compression numbers

Any smoke

Funny enough not at all aside from the tests I ran there is no sign of any problems.

Stick to the spec you got with the studs. I've always torqed to 65 and they've been fine.

Update
Got the cosworth gasket installed did compression test similar results did a wet test on 3&4 and only increased 10psi. Bottom end is good. Then before the intake and exhaust manifolds were installed I did a leakdown. Cyl 1 = 10% 2= 18% 3&4 = 75%. Except this time only place heard air was from the exhaust valves? Last time I had the turbo on so the air was hitting the turbo(restriction) and turning 180* into the other cylinders. I'll call the machine shop tomm and hopefully they will take care of me. LESSON LEARNED : turbo guys REMOVE the turbo as it is a restriction and not allow the low psi air to escape out the exhaust pipe as in a normal leak down test. I can finally rest as I know the problem. I hate that I had to buy a gasket but I feel it's a bit better than the ve mls.

Thank you everyone for your help and you guys are awesome. I'll keep y'all posted along the way.

Just to keep everyone in the loop. Got the head put back on today after the machine shop gave it a once over and my leakdown percents are 25-20-20-40. The car hasn't been ran at all so I think I can live with the 40%. Thanks again for all the help. Will post results of a proper warm leak down and compression test as I know that cold leakdown tests don't give an accurate number.

after running the car ive finally got great compression. now my problem is it breaks up bad at wastegate pressure. tried new plugs and same results using ngk 7s at 0.25 car is gated (tial f38) at 10psi any thoughts? also tested the coil resistance and it checks out. I did reuse the intake manifold gaskets (they were new on the rebuild and looked good). when it breaks up the wg opens and sounds like its cutting on and off and backfiring out the dump pipe(car does NOT backfire though) ewg is only on spring now no MBC. any advice would be appreciated.

Around what psi and rpm.

its at 5k right at wg presssure i can brake boost to 8psi and hold it no prob and i can reach out first w/o boost to 7800rpm and runs fine. I did notice that one coupler was clamped to the bead of the pipe when I took the EWG out. I plan to bench test the EWG tonight and have fixed that coupler. maybe that was the problem if the ewg checks out ok?

Sounds like boost leak

great thanks for the response I only took 2 couplers off so it must be one of those after i bench test the ewg ill check all the couplers again thanks.