CHEVY New Carb Install- too high engine RPM


G-Body Guru
Sep 6, 2020
Well hello again!

It's been awhile! Sadly not much time to hop on with studies.

Anyway, I swapped my old Quadrajet for a new one, and despite the cost, I kept the CCC version.

Well, now I'd like to tune the thing, but as soon as I start the engine the RPM's go crazy!

I will check again for vacuum leaks, but I'd like to know what screws go to where, and how to not make my fūcking engine blow up haha.


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Oct 1, 2022
To over simply ask is your choke set to tight try putting a screw driver down int that area between the edge of chock and starting if the idle goes down did you get a good pulloff pod or do you know where the high idle cam screws at ? will backing this out solve the issue .your car got egr you didn't squish it did you ? Could be seating issue who knows we're the secondaries butterfly warped when installing. Simple questions look down the barrels are the butterflys seated? wait is this one of those fake quadrajet 2 barrels if so nevermind secondaries. Some quads came with a stainless plate you had to use okay .uh never use permatex no.1 on a carb gasket yu will have a bad vacuum leak the following day / trip ect.
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Oct 14, 2008
They may just have the fast idle screw cranked up too high. Try adjusting that down a turn and go from there.
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