Flat top piston is best , dome impedes flame travel. The problem with 383's is piston selection sucks. There is no piston out there that has the same compression height as a stock 383HP piston and the factory lied about the compression ratio.
There is a member that has a piston available that is close to stock , you want one wit ha small valve relief , 3cc would be best .
The best piston would be a custom Diamond with a step head dome for use with the 906.
What is your budget ?
Just reread your post , you are in Cali , land of crap gas , you need to build it right so it will run on the swill that is at the pump.
JohnRR thanks for the information,
Who is the member that offers the good piston that you mentioned? The car spends most of its time in Arizona, I think the gas quality is better plus I usually mix 25-50% Racing fuel anyway.
Don't want to spend a ton on it but get a nice build. Is there a good flat top that is readily available for the 383, it seems that someone has referenced a Speed Pro piston in the past they have had luck with.
