Since I'm going with the Comp Cams retro-fit roller cam (CL35-421-8) can I use a Synthetic oil right from the get go? I know I still have to use the Comp Cams break-in additive. I was thinking of going with AMSOIL 5W-30 Motor Oil (ASL).

 

You don't need to run any break-in additive with a roller cam. Roller cams and lifters are hardened steel and aren't subject to wear like flat tappet setups.

But yes, you can run synthetic as long as you're just doing a cam swap, not breaking in a new engine.

 

Its a complete new build... clean block starting off with.

 

Oh, then no, no synthetic until at least 8k mi (I'd recommend 12k). It takes about that long to break in a new engine completely, and the synthetic won't allow enough friction for that to happen