383 Problems..
Remember machine work will be a little more due to boring the block before honing. I see Texas Speed lists a 384 3.910 Mahle piston. Just a alternative for you. Either way you do it it would end up costing close to the same give or take a few hundred.
The engine was pretty warm when i performed the tests. We did a wet test on one cylinder and i gained around 45psi just doing a wet test. I was told that altitude wont effect it but about 10 15 psi? I cant remember what the gaps are on the rings..another guy at the shop we built it at did the ring filing. Im heading back to around 1200 ft elevation here for week here pretty soon, i may run a compression test down there.
Whats your static compression ratio and what's your cam specs? , those are all real low, piston to cylinder wall clearance and correct ring gaps, and having pistons with offset pins are absolutely critical to good ring seal in these short cyl long stroke engines imho, If I were you id be using the new wiseco's and their gfx rings. 017 top and. 019 second for NA and. .0035 p-wall clearance imo
My best guess assuming your head's were milled. 030 is you are right around 11.05:1 with -6cc mahles and stock head gaskets with a zero deck, your dcr will be 8.2-8.4 range so yeah your comp leak down readings show some serious issues, good luck getting it fixed, were you happy with the power?






