Hi, im a new member so this is my 1st post.i'll give you guys some back round on my engine. it a 350 with stock heads, edelbrock intake and an edelbrock 600 carb, with accel breakerless distributor and superstock wires ans champion plugs and a weakening th350 tranny. ive been working my chevelle for about a year know and this just started happening a month ago. Lately since the weather has gotten warmer i noticed a hesitation problem when punching the gas from a dead stop. it runs fine when its still cool but after 20 or so minutes of driving it hesitates at 3/4 throttle and higher. only at a dead stop though. If I get on it on the freeway it's fine.
Any ideas? i made sure my fuel line wasn't hitting the coolant hose either. Any input would be much appreciated.
- Brandon

Hi Brandon graemlins/waving.gif , welcome to TC.

On the front driver side of the carb is a link that goes to an arm with three holes in it. That's the accelerator pump arm. Try moving the link to one of the other holes. This will increase or decrease the pump shot and may help. The other thing I'd look at is the springs on the air door. I can't tell you if a lighter or heaver spring will help. This will effect the timing of the opening of the door. Actually, I've never messed with mine.

I've had an Edelbrock on my driver for 12 years and have never fully cleared up a slight off idle hesitation problem it has. It is much more pronounced in hot weather than cold. Carter AFB type carbs, which the Eddy is, seem to have these nagging little hesitation problems. If you have a more than stock cam, you might try setting the timing to about 12-16º of advance. I don't know if that will help but it's easy to do and generally increases power.

thanks for the tips Pat, i had forgotten to mention that i had already moved the pump lever to the lowest notch with only a little improvment. i do have a very mild cam so i might try more timing.
otherwise i just might invest in a holley or demon carb .thanks for your help. :D
-Brandon

70chevelle
Richen up your idle mixture screws and see if that helps.