I have a strange issue with a new Holley 770 ultra street avenger.

When holding the peddle to the floor gas comes out the vent tubes and
into the air filter.

That carb has been dyno tuned and runs great, unless you hold the peddle to the floor.

Any idea what is going on?
Why does it act like the floats are sticking, but only when held open?

 

Are the floats adjusted too high?

 

I don't believe so. It has the site glass type.
They are half way up the glass. Exactly were they came from Holley.

 

What type of fuel pump? If it's mechanical, it may be too high a volume when the engine rpm's come up higher. Or even an electric could be slightly too much pressure. Holley's don't like pressures over 5-6 lbs.

 

So then yeah, the floats are set too high. The gas level wants to be at the bottom of the sight glass. The way you would set the level with the plug out, would be so the gas juuuuuust starts to dribble out of the opening. Being in the middle of the opening would be more of a flow instead of a dribble.

 

I get it to where it only dribbles if the car is rocked.

 

I was wondering about the fuel pump, but it is a stock mechanical. I have I high flow
edelbrock on my Camaro and it doesn't have any issues.

These new sight glasses are 3 times the size of the small screw you take out.
If the fuel was at the bottom of the site glass it would be a full 1/4 inch lower then
the type with the screws. I am not apposed to lowing the float level, but I dobt that it the issue. No one but me has ever messed with this carb. Floats are set in the same spot as the day I got it.

It also does not flood under hard breaking, as it typically would with floats being to high.

 

I'm not sure you understand the way those sight glasses work. The sight glass is larger, but it's like a magnifying glass, so if you see fuel in the glass it's being magnified from the small hole. Once the level is dropped to the bottom of the hole by adjusting, it wont be 1/4" low, it will be at the bottom of the small hole. Your glass is much larger, but the hole still is the same, and the fuel level will be the same if adjusted.
Take a pic at these:
http://cgi.ebay.com/ebaymotors/CLEAR...item256758bf3e

 

gfrench, without seeing, I can't say what you're looking at on your end. I put clear sight plugs on my Holleys, and looking through the plug, I can still see the actual bottom of the hole.

 

I did not istall clear site plugs. The holly 770 comes with a "Site Glass" They do not come out. Says all ove rthe manual do not remove them.

Anyway, I copied and posted the info from Holley.
Fuel level should be dead center of the site glass.

Here is the carb. I dont feel it is the float level.
Holley Performance Products 770 CFM Ultra Street Avenger Four Barrel Carburetor - Red™ 0-86770RD