Horrible01

Ok here is the situation, I got a 570 street avenger on a small block 350. I wish I could tell you the specs on the motor but I can’t because I did not build the motor myself. I can tell you that there are dart heads on the motor and decent cam in there. And the compression should be around 9.5 to 1 or maybe even 10. With that said I will also admit that I think the carb might be a lil small fro my application. Anyways I just upped the size of my discharge nozzle to a .35 from a .31 and I saw huge improvements in acceleration if I don’t smash the throttle down. BUT the engine still bogs off the line a little. Before the change the motor would bog really really hard but would pick up. When the car does get going tough it hustles its butt off. My question is should I go up a step to the .37 discharge nozzle or is it possible for there to be another problem all together. I know the 770 street avenger only has a .35 discharge nozzle so I feel like im putting a band aid on the problem instead of fixing it. Any help would be appreciated. O and im using the stock 305 tbi fuel pump which should be more than enough to feed the carb.

five7kid

iTrader: (14)

Is your problem only when going WOT from low-RPMs, or anytime you press on the accelerator?

If only going WOT, then the problem is your secondaries opening too quickly - hard to imagine with a 570 on a 350, but still possible, I suppose.

If anytime you press the accelerator, I'd check the accelerator pump adjustments first, then for any vacuum leaks.

What distributor are you using? Are you using a fuel pressure regulator? Are your float levels set properly?

Horrible01

Full msd Ignition 6al box and the blaster coil 8.5 wires ect ect.The floats are dead on and the regulator is set at 7psi (maybe too high but it should not affect anything) the accelerator pump hits as soon as you tap the throttle. Now the power valve on this carb i think might not be suitable for my application. I’m thinking i need to go down from a 85 to a 65 power valve. Problem might actually be with the power valve and not the accelerator pump. Just about anytime i get on the throttle it boggs. is when i have this bogging problem. I’ll try to put a quick video together tonight and post it. o and one more thing... my manifold makes about 12 in. hg thanks for the help so far.

sofakingdom

iTrader: (1)

Going to a lower number power valve will make the problem worse; what that will do, is require the vacuum to drop EVEN FARTHER before power enrichment occurs.

The accel pump is nothing but a crutch to cover up the very brief interval of time between when you put your foot down and when fuel begins to flow through the main system. If the carb as a whole is working right and tuned properly, the pump is almost unnecessary. If you think you're having to dink with it to "fix" something, then there's some other actual problem that you're just band-aiding with it.

Do a search on my userID and the phrase "transition slot" (or maybe "slots"). Read all my posts on how to tune Holleys. Put the stock squirters back, then go do what I say to do, and come back and tell us how it worked.

five7kid

iTrader: (14)

But what distributor????

Horrible01

its an msd pro billet distributor