getting ready to try a custom 850 DP I used run on my sons BB race car, just wondering if anybody has a baseline on jetting, will have a primary power valve, 509, stock rect heads, and roller cam, factory dual plane alum. intake, stainless marine full headers..thanks Rob

84's all the way around.That should be what you'll need.

84's all the way around is what my 555 has in its 850 DP. Single plane intake and Lightning Headers. Square port Merlin heads. A/F ratio is about 12.5 to 1.

is that with running just a primary power valve ?? Thanks Rob