I have a stock '68 350 with a '73 455 QJ I put on a few yrs ago and never got around to getting the smaller QJ rebuilt. My question is... I have a TA212 cam that I (hopefully soon) will install in the 350, both carbs need rebuilt but I can only afford to have one done. so which one would work best for the 350? is the bigger one TOO big? it seemed to running fine with it so far.
choosing between those two carbs in stock form I would use the 73 455 carb. The Qjets air flap secondary design makes it a variable-cfm carb so the 800cfm wouldnt be "too big", the motor will only take the air it needs. Its more about the calibration.
My vote would be to stick with a q-jet calibrated for the 350, if that's what the "other" carb is. The differences in the idle circuits can cause issues when swapping a big block carb to a small block & vice-versa. Devon
