alright, ive been reading alot of the posts here and i came across something ive never heard of before. ive been haveing this annoying hesitation from idle to acceleration for the longest time now and i am completely sure its not a vacuume leak, its not my idle mixture, its not my timeing, its not my plugs or ignition system and its not my fuel pressure. i am about 95% sure the problem lies within my carb. a guy on one of the other posts mentioned an accelerator pump being the cause of this, but he was talking about a holley carb. i seriously know almost nothing about the inner workings of carbs, but i am trying to learn. does my edelbrock 600cfm (1406) have an accelerator pump? this carb is totaly out of the box, and the only things i have adjusted is the idle mixture screws and the choke(yes, its fully open when its hesitateing). also when i am at a stop light, every now and then the rpm's will bounce down then up like its gona stall for half a second, when it starts doing this its guarenteed to hesitate when i step on the gas. some times though the car drives perfect for a while, but eventualy it will start doing this again. is there something inside my carb that i should be checking/changeing due to it being straight from the box? it says its calibrated to run on a edelbrock performer RPM manifold, mines only a performer manifold. basicaly the two things that were mentioned about a hesitation are the accelerator pump and the float. any ideas? any help at all would be greatly appreciated.

 

Yes, it does have one. The DSL front corner theres a rod with 3 holes. Move rod up to decrease pump down to increse. Still could be timing, just because its set @ X* still doesent mean its right. Ive totally eliminated some bogs off idle just by bumping up timing just a hair.

 

its set at 8 degrees, but this shouldnt matter if everything is working like its suppost to. ive been told by alot of people that your suppost to run as much timeing as possible without causeing the engine to detonate. if i lower the timeing to 4 degrees, oddly it runs better but i get horrible gas milage and performance. the performance/ gas milage i get now is awesome, its just this stupid idle-to-acceleration problem. from what this other guy described, the accelerator pump isnt shooting enough gas into the "bowl" for the transition between idle and acceleration.

 

Ya know it could very well need a pump adjustment. Although I havent had to change pump shot to get one working. Mostly just problems with the metering springs cause off idle and part throttle/off/on hesitation with my situations.