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Discussion Starter #1
Got everything running pretty good, but still working out a few little issues. When I'm cruising very light throttle and then go to give it part throttle to accelerate there will be a pause....like almost dies...then will pick up and accelerate fine. If I stab the throttle it doesn't do it, it just kicks down and goes. I'm thinking it's the accelerator pump on the carb, but thought I would check to see if anybody else had any thoughts? If those of you agree that it could be the accelerator pump, if you have any suggestions or advice on how to adjust it or what to check that would be helpful.
Thanks
 

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Discussion Starter #2
Responding to my own thread lol. I adjusted the accelerator pump and it made a bid difference. I made sure it wasn't bottoming out, I still feel a small hesitation but no where like it was before. I'm thinking I could probably adjust a little more, but may have to up the size of the accelerator relief or put a different cam in it.
 

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Adjusting it as you noted can make a big difference. You can also get bigger ones that give more volume. You might also go up two jet sizes and see if it likes it better.
 

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i think youre on the right track but also make sure your vac advance is working
 

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Discussion Starter #6
Adjusting it as you noted can make a big difference. You can also get bigger ones that give more volume. You might also go up two jet sizes and see if it likes it better.
I'm going to look for the kit today that has the bigger squirter and cams.

What is your engine/carb/intake manifold setup?
306 cid roller
AFR 165 Heads
Lunati 218/218 .525 cam
C4 Stage II
3.55:1 Rear
RPM Performer Air Gap Intake
Holley Street Avenger 570


i think youre on the right track but also make sure your vac advance is working
Thanks will double check.
 

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Discussion Starter #8
Are you running a carb spacer? If so, open or 4 hole?
No spacer it is open as it is an Edelbrock Performer Air Gap intake.
 

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If you have the clearance, try adding a 1/2in or 1in 40 hole carb spacer.

This really helped my 289 and I also put one on my friends 408 and made a big improvement in off throttle response.
 

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Discussion Starter #10
If you have the clearance, try adding a 1/2in or 1in 40 hole carb spacer.

This really helped my 289 and I also put one on my friends 408 and made a big improvement in off throttle response.
I have almost all of the issue resolved, talked to Holley tech support today and they are sending me the next size up squirter for the accelerator pump. I'm not sure I can go much higher with the carb if I put a spacer in it as the top of the post for the air cleaner is very close to the underside of the hood with the Air Gap Intake. Thanks though.
 
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