With my combo being said I didn't say I was running a holley 650 double pumper band I'm thinking of running a half inch spacer to get the heat off the bowls of the carburetor
I read that The intake is sensitive to carb tuning I will be running jet extension I will be running in Southern California where should I start with my jets??

The Sierra Pelona Mountains (to the north) can be seen in parts of the San Fernando Valley from the gap between the Santa Susana and San Gabriel (Newhall Pass). The valley's elevation is about 250 - 1,200 ft. above sea level.