I have a 84 Z-28 with a 350 ci. bored .030 over,flat top pistons, L31 vortec heads, Eld. preformer intake, 600 Carter comp. carb.,Accel ignition, headers and I just am finishing putting a Comp. 268H cam in it. Iam in the process of timing and tuning the engine. I realy need to know how much (total timing) to put in the engine! I would realy appreicate some help. Thanks NORT P.S. The lift of the cam is .477-.480 .

 

I'd start with 34* and go from there. Everything I have heard about vortec heads is they don't need a lot of timing dew to the combustion chamber design. You might also need to think about the whole advance curve sence you are running higher than stock compression and no egr. Might have a problem with detonation if you not careful.

Steve

 

I read a test and they had the best luck in the 32 to 34 degree range.