my 351w does not want to take off like it should. it will be a little bit sluggish on the take off and the secondaries will not kick in until about 2000rpm. but even then the engine does not want to rev up like it should. if your cruising in 2nd and floor it, it wont do anything but speed up a little bit. the engine has a # 80145 600cfm holley dual inlet, and it has racing bowls. i have a weakest vacuum spring in the carb that came in the holley kit, before that the secondaries wouldn't even open. I've had people tell me all different things to do, adjust my floats (which i've done), i don't have enough vacuum (i have enough). and i just need a 750cfm and my carb is to small. but others have told me that should be enough carb for my engine. any help would be great. my engine has eldbrock parts, stock ported heads, ported manifolds, torker 2 cam adn intake.
that carb should be just fine. it may be alittle to small for high rpm use but that would mean that your problem wouldnt exist. it should be very snapy and responsive at cruising rpms. was the carb new or used? what is your timeing set at? is the advance in the dizzy working? Have the jets in the carb been changed? is this a new development or has it always ran like this?
Sounds like timing,carb should be fine considering you have production heads/exhaust manifolds.I'd put a timing light on it & go from there.
Timing here too. It sounds like it's retarded too much. And/or the advance mechanism in the distributor isn't working. The 600 is fine for all but the upper rpms. The 80145 is a great carb.
the carb was new i got it from 69 ina 1/2 from here. im running the Mallory comp 9000 distributor, pro master coil, and the hyfire original box. this is a new problem, i had a 650 carb but the secondaries were jammed so i got this carb and it has had this problem since. but the only big thing different was i has the turn the distributor 180 because the first time i went to time it the timing mark was on the other side. but before i turned it 180 it idled nice but now it idles kinda rough when i try to get the timing at 0 it stalls out. i dont know if this helps but if you floor it from a idle in gear it will stop and then go and once in a while it will stall out. the last thing that has gone away now is when i start it once ever like 4 starts if you let it idle for a couple minutes it will get out of its grove and start idleing really rough adn you have to rev it up and hold it for a while to get it back idling nice. i have a eldbrock dual timing chain roller. the only thing i did wrong was put the fuel pump exentric on backwards. but im going to fix that now while i have the car apart.
im sure its your timeing now. you need to pull the dizzy. put the motor on top dead center on #1 cylinder. put the dizzy in with the vac advance if it has one pointed towards the drivers side headlight and the rotor pointing towards the front pass side carb stud. that should get you back to where you can time the car. i dont know why but i have seen what you describe. where the distruber is in 180 out and you just cant get it to time correctly.
While your fixing the fuel pump eccentric ,,, double n triple check timing gear marks. Then double check distributor timing. Many times marks that line up are not lined up,,, dont ask,,, Good Luck.
