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Rebuilt my Q-jet, need some help now.

1082 Views 12 Replies 4 Participants Last post by  SWHEATON
I rebuilt my Quadrajet to Cliff's specs for my car(Trans-am). I believe the float is set right. Its got a Carter 120gph fuel pump. New jets and rods. New accel. pump, basically all new inside.
When I first started driving it would buck when trying to cruise at light throttle. I turned to APT screw out until that quit.
The problem I am having is with the Secondaries. If I drive along at 30 in first gear it will spin the tires like crazy, but then if I shift into second and get back on it, it bogs. Or if I try to punch it in 2nd or 3rd gear at say 2500rpm it will bog but it sounds like the secondaries are opened, then when it gets up around 4 or 5K it will pull like a freight train. The same happens in 4th at 3000rpm.

Would the spring that controls the butterflies in the air horn need tightened more? Or would it be the choke pull off the lets them open, Cliff gave me a new pull-off in the kit. Any suggestions? It gets very expensive testing this at $4.30/gal for premium. Fun,:) But expensive.:(
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Yup,your exprieincing the good old QUADRABOG that cause the the upper sec air valve being ad too lose resulting it openign too quickly.

Then the sec gets a quick rush of air but the secondary fuel hasnt caugh up yet thus leaing out the secondary mxi making it bog untill the fuel finsally get there.

Simply tighten the upper sec spring a 1/4 turn and try it it out ,if it still bogs now tighten it in only 1/8 turn segments just untill the bog stops but the sec are still opeing fairy quickly and thats the sweet spot.

Good luck.

Luke,you need to try adj the upper sec valve,it usually only takes a few tweaks to get it correct and from my experience 9 of 10 times doing just that will fix a quadrajet secondary bog issue.

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