What jets should I use?

[Spudboy]

I have a 1970 GTO Judge with the following:
400 engine (1972 block, 1969 #62 heads).
Ram Air lll cam (408 lift)
Headders
Automatic trans
3:42 open rear axle

Generally stock, used mainly for cruising and car shows. I normally run 71 jets with #45 primary rods in my q-jet. I am building a 1973 Buick 800cfm q-jet (7043240) to put on it. It specs at:

73 jets
44b primary rods
CT secondary rods
M secondary hanger

Should I stick with the 73's or could I just drop in a pair of 71's?

[Cliff Ruggles]

Jetting should be based on carb being used and application.  For that carb number 73/44B will be just a tad lean at part throttle.

I would remove the factory APT screw from the baseplate and contact us for an external APT screw and tuning parts for what you are doing.

Having the APT functional will allow external adjustments with the correct metering rods for full control of part throttle A/F without taking the carb apart.  It's a great feature on those units.  I would also get one of our rebuild kits for it while it's apart.....Cliff

[Spudboy]

I did fail to mention that I did buy a Cliff's rebuild kit and a pair of .036 idle down tubes to boot.