Originally posted by ChevyPower
I have a 750 cfm Rochester Qaud. carb. and I need any suggestions how to tune it. The carb. is on a '72 454cid egine with a automatic trans. I can tune the idle fine, but beyond that I dont know the steeps to make other adjustment. My attempt is to get a better reaction from idle to flooring it.
if its the Q-JET that you've got ChevyPower you have the 2 hole pump rod to work with, but the main thing on the Q-JET is the secondary butterfly adj. there is a spring adj. to it and if its to tight you wont have full 4 brl. use, and if the butterflys are to loose then you are gonna bog the motor down when you floor it. the back butterfly's shouldn't work at all with the choke on so you need to worm the motor up and then tap on the secondary butterfly's with your finger and if they fill loose or sloppy then you will need to tighten them up. to get the max. out of the Q-JET. you can loosen up on the secondares untill you bog the motor down and then tighten it back up a little and that should be the max. fuel that your motor will burn. i wont go into that now until you check the tension on them, and let us know. make sure the choke works good, get the pump rod adj. properly, and adj. your secondery butterflys right and thats about all you can do to a Q-JET externally. JMO not trying to steal the thread.