I was advised by Holley that my off-idle partial stumble could be a result of imprper float setting.

I know how to adjust the float, the only thing is, i dont know wtf im looking at in the sight holes.

Is there a better way to tell if im looking at fuel, or no fuel. They say its supposed to be set at the bottom of the float sight screw, but i can't see the fuel level.

Also, when i shut the car off and unscrewed the float retaining screw, fuel came out of that...does that mean maybe float level is too high?

There has to be some other way to set this besides looking through some POS plastic screw they give u with the carb.

If any of you holley guys can help, i appreciate it

 

Ahhh, nevermind guys, i didn't know you could adjust the float with the sight screws completely removed. I thought gas would shoot out lol. All is well, for now. i will try again, after i get out of the damn numerical analysis joke of a class

 

Well, adjusting the float level definitely helped. The hesitation is alllllllllmost completely gone. the rear float was way down and the front i pulled it up a little too, so the fuel is very slowly trickling out each sight hole.

question tho: should i step up a size or 2 in jetting?

 

don't know about the jetting. check your plugs after a long drive maybe. no other ideas.
as towards the way you adjusted that seemed fine. just at the bottom of the hold and when you tap the car on the side it should spill.

btw. if you have the screws that go in there replace the sightplugs with the screws. the sightplugs are only meant for adjusting.
Over time they get dark/blurry and you can't see a thing anymore,. even worse they get hard and you can;'t remove them anymore without breaking

 

the jetting on the 570's is really small, so going up 2 numbers in the front and back certainly aren't a bad idea.

how is your accelerator pump adjusted? when the throttle is closed there should be no slop in the arm, but it should also not be already pushing the diaphragm in either. and as soon as you bump the throttle any amount (and i mean even the smallest amount) you should see gas shoot out of the 2 discharge nozzles which are in the primaries, right in the front, and under the choke plate.

 

Yeah ive heard horror stories about those clear sight plugs. ive got the gold screws in.

When i blip the throttle i see a strong healthy squirt coming from each nossle.

I am 99% sure increasing the jet size a little will solve the problem, i just wanted confirmation that the jetting that comes in it is a bit small.

holley says they calibrate their carbs at sea level...i have read other forums where guys claim its as if they calibrate them for 10,000 ft, lol. i dunno about all that, but i definitely need a bit more fuel at partial throttle.

thanks for the responses

 

you should also check your idle vacuum and see if you have the right power valve in there. i'd probably do that before you change any jets.

 

Ok well i finally got around to getting a vacuum reading taken at idle (in gear).

i dont know much about holley's, but from watching a video, seen below, on how to choose the right power valve, i learned that your power valve is chosen simply by dividing your vacuum reading by 2.

http://www.youtube.com/watch?v=6vKlAnKdcB4

the engine vac at idle in gear was 13-14", which would require a 6.5 power valve, or #65. according to the chart they sent with the carb (570 street avenger) it has a #85 in it right now.

whats involved with swapping these little guys out?

 

It is very easy to change the power valve. Just remove the bowl, (cut a pop can about 2 inches from the bottom and slide under bowl to catch gas) The power valve then threads out. Very easy. By the way, was your car flooding at all when at idle. I have the same off idle hesitation, and was planning on adjusting in the spring.

 

the spring will have no affect on off idle hesitation.
that's either down to incorrect curb idle screw setting, idle mixture or float level