Qjet bog
Thread Starter
Racer
Joined: May 2008
Posts: 318
Likes: 0
From: Wheaton, Illinois
Qjet bog
Just installed a 78 L82 qjet on my 79 vette. Car is stock except for a mild cam. The problem is from a stop or anytime I get on the car its has a bog. I adjusted the secondary air flaps to the tightest setting and installed some medium secondary rods to eliminate most of the bog, but still cant get all the bog out. Any suggestions. Al
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Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
You probably need to replace the seal on the accelerator pump piston. When you depress the throttle, it puts a shot of 'raw' gas into the intake to eliminate that kind of bog. Take off your air cleaner [engine OFF], look into the carb primaries and manually pump the throttle linkage. You should see a pretty good squirt of gas going into each of the primary bores. If the stream is weak (or not there at all), that is your problem. Otherwise, your problem is one of timing adjustment.
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,391
From: At my Bar drinking and wrenching in Lafayette Colorado
- Inadequate timing advance/faulty timing curve/faulty vacuum advance
- Defective accel pump
- Lean primary jetting (jets and/or rods)
- Low float level
- Low APT setting
- Lean secondary rods
- Defective choke pulloff
- Improperly set secondary rod height
- Incorrect secondary airvalve spring windup
- Low fuel pressure
- Plugged fuel filter
- Secondary throttles set to open over-center
- Damage to secondary discharge tubes
- Damaged secondary rod cam
