Chevy 355 with Crane Energizer 272 H10. How do I read the cam card to figure out what my timing should be? I think it's a little off and need to tune. I have this cam, stock '71 heads with 76cc chambers, and flat top pistons with two half-circle valve reliefs in them. I seem to diesel a lot when warm, and have been told it's timing or compression. With such a big chamber and such in my setup, my compression ratio can't be that bad that I have to run 93 all the time to avoid dieseling (and it still does sometimes), right? I've tried the DCR calculator but I always do something wrong, always get NaN:1 as my ratio...eh. So, what's a good timing to shoot for? Thanks.

Please post come specs of your combo..

350 sbc bored over to be a 355
Flat-top pistons with two valve reliefs
Crane Energizer 272 H10
Rochester 2-bbl carb (2GC)--about to put on a Q-jet
Factory Iron Intake
Stock heads (I'm guessing 1.72 intake valve setup) with 76cc combustion chamber
Stock stall (1600-1800)
TH350
2.56 rear
1 5/8 headers to dual exhaust (straight pipe/glasspacks)

Unsure what else is needed, unless maybe like more cam specifics..thanks.

Does your cam idle high, have poor vacuum, and not come alive until about 35 MPH?
The Crane 272H should idle about 600-650, have at least 16" of vacuum, and pull OK from idle with a stock converter.
Let me know what it does.....

UDHarold