I just rebuilt a 351 W (dont hate me) and am using stock 4bbl manifold and exaust manifolds. I put in a comp cams EX252 cam, Ok if you start it without touching the gas it runs smooth but if you hit the gas, the car shakes and runs like crap and wont return to normal. Then if you shut it off for 10 seconds and start it again it runs smooth, until you hit the gas. I think it is my carb, it a new EPS 750 with electric choke.
Digger
Digger
Its possible ther is some trash "dirt" in the carb or the floats are screwy. "Ah the ease of a holley float system 
"
It could also be a vac leak or a breakdown in the ignition.
Edelbrocks 99% of the time if your not picky like me "1%" run fine out of the box just a set idel& A/F and your ready to go. If you have another carb laying around I suggest you try it and see what you can eleminate by using a known working carb.
Good luck!
SSC
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85 Camaro, 355/400 "drag car" in moth ***** 13.1@ 101mph on its last season run.
Plans: Possibly add N20 for next season.
82 Firebird, 305/350 currently moth balled.
Current plans: Rebuild 305 with flat tops instead of the dished "cups" for pistons or slightly built 327 with the 58cc heads from the LG4, Upgrade the 2:73 to 3:73 or 3:42 and replace the turbo 350 with 700r4.
"Web site under construction"
G0D Bless.
"It could also be a vac leak or a breakdown in the ignition.
Edelbrocks 99% of the time if your not picky like me "1%" run fine out of the box just a set idel& A/F and your ready to go. If you have another carb laying around I suggest you try it and see what you can eleminate by using a known working carb.
Good luck!
SSC
------------------
85 Camaro, 355/400 "drag car" in moth ***** 13.1@ 101mph on its last season run.
Plans: Possibly add N20 for next season.
82 Firebird, 305/350 currently moth balled.
Current plans: Rebuild 305 with flat tops instead of the dished "cups" for pistons or slightly built 327 with the 58cc heads from the LG4, Upgrade the 2:73 to 3:73 or 3:42 and replace the turbo 350 with 700r4.
"Web site under construction"
G0D Bless.
Senior Member
Carb be a little big for that cfm/cam combo. IMO trade it fr a 600cfm or sell it and buy a 600cfm.
It runs like crap until it warms up.Then when its warm shut the engine off, wait then start it up and it runs fine, unless you hit the gas as if you were kicking it out of high idle. Could this be an ignition issue, or my electric choke. or could it be possible the metering rods are sticking up hen you hit the gas. My vacuum lines I dont think are a problem, all I have are vacuum advance, pcv, brakes, and tranny. so I dont know. And for the over carbing issue, I have 2 other EPS 750 on my 350s and they run exellent, one is manual choke the other is electic. One of my cars even has a GM 151 cam and it works great.
Supreme Member
The shaking thing sounds like something other than carb problems... a little shaking will point to vacuum leaks (a miss now and then) but at higher RPMs it will dissapear. If its alot of shaking then it's probably ignition (dead cylinder).