a good start would be the jets from a pre-smog era engine: #71 prim jets plus #45 metering rods (rods could vary a thou or so either way) as a check look into what the '66/'67 ohc pontiacs used (not the '68 & later as they were into the smog era and as we all know leaner and needed all kinds of crutches such as heated air cleaners etc).
What size primary jets and rods did you use with the 273 inch Mopar carb?
