My 3310 holley is getting lots of gas into my engine after shut down, I have had it off 3 times since the prob started. It has all new gaskets, needle and seats are new, new filter, floats are set a hair low and this still happens. Gassed up 2 sets of plugs already, it runs great until I shut it off and wait about 15 or 20 minutes. After that its hard to start from the flooding. I have a stock mechanical pump with no regulator. The only thing I can think possible is that my headers are pretty close to the gas line, although I have insulation on the line.

Should I re-route my fuel line? maybe a carb spacer to keep heat off the carb? I have a drop base air cleaner, doesnt that trap heat around the carb too much? This is so frustrating, I just switched to Acdelco FR3LS plugs from the champions and the car runs better than ever I dont want to foul them! Thanks guys

That's a tough one. If the float blowls are overfilling usually gas spills out of the vent, runs down the sides of the carb, and onto the intake manifold --- not usually into the intake.

How do you know gas is running into the engine after you shut it down? Are you just assuming that because the plugs are getting gas fouled?

I would definately re-route your gas lines just on principle alone. If its too close to the header it needs to be done anyway, if it cures your problem that would be a bonus.

One test you might try is to pinch off the fuel line (or disconnect it if you have all hard lines) between the carb and the fuel pump. Then pull the site plugs out of the side of the float bowl and check to see how high the gas is in the float bowl. Then come back and before you restart it see if the level in either bowl has changed --- if it is the same the carb isn't leaking into the engine. You could do the test again with the fuel line "not pinched" off, to see if the float level goes up with the car off.

Just a couple ideas.

Thats excellent trouble shooting skills you have there Eric, I will try that out. Im sure its dripping because If I turn it off after driving, and check a plug it looks fine, after leaving in the engine for 20 minutes or so and then pulling it, its real gassy. And when I removed the carb after it sat for a few days inside the intake was extremely gassy and gold colored, along with wet fouled plugs(not oil)

Im upgrading the fuel system before next saturday, so that should cure it. Ive been trying to decide between a Holley blue electric on Ebay for $45 with all new aluminum 1/2 line, or just a holley mechanical 110gph and re-route my 3/8 line. A friend of mine just put all new 1/2 aluminum with a holley electric and its awesome.

Check the venting in the gas tank. Exhaust heat may be expanding the gas fumes in the tank and creating large pressure, forcing the fuel in the line by the float valve.

remove the gas cap and see if it still floods.
god luck
joe c