Carb Tard, need help [Archive] - Team Camaro Tech

: Carb Tard, need help


Paul H.
May 14th, 04, 11:58 AM
First of all, I know nothing about carbs so bear with me. This is probably something easy to fix. I have a Holley 650 cfm, dual feed, vaccum secondaries, electric choke running off of a mechanical pump on a SB 350.

Whenever I'm sitting at idle and then 'goose' it, it stalls for a second and then jumps on in. It seems like I'm not getting enough gas or too much air when this happens. If I accelerate slower, there's no problem. Any ideas on what the problem could be? This is a newly rebuilt carb...does it need bigger jets?

J early
May 14th, 04, 12:05 PM
From one Tard to another, I've heard this can be from a lean condition.

Paul H.
May 14th, 04, 12:18 PM
How is a lean condition fixed?

paulm
May 14th, 04, 01:05 PM
Hopefully one of the Holley guys will jump in, but there is a little accelerator pump that is supposed to squirt in a little extra fuel when you nail the throttle to get you over the dry spot until the carb can catch up. In theory this would fix a bog as you describe, but there could be other causes as well.

BPOS
May 14th, 04, 01:27 PM
Check out the advice given by Eric68 in this thread---worked for me!

http://www.camaros.net/cgi-bin/forum/ultimatebb.cgi?ubb=get_topic;f=4;t=006236

DjD
May 14th, 04, 01:33 PM
Pauls got it... The accl pump is there to transition off the idle circuit. When the throttle blades go WOT air moves into the carb faster than the fuel can so a temporary lean (J got it!!) condition is created until the fuel catches up. Make sure the accl pump starts squirting fuel just as the throttle is cracked. Also adjust it so you have about .015" clearence when the throttle goes WOT. The next issue to look into is the duration of the squirt produced by the accl pump. There are little colored cams that mount onto the throttle blade shaft that control the duration... The last part of tuning the accl pump is the nozzle size. You can change squirters to control how much fuel is delivered.

Here's some info on the Holley site that may help... http://www.holley.com/HiOctn/TechServ/TechInfo/TI-221.html

Paul H.
May 15th, 04, 02:00 PM
Cool, thanks for the help guys.

oger
May 15th, 04, 02:19 PM
Is it worse when it's cold? If it gets worse as the engine warms up too much fuel can cause the same problem.