excessive flooding

I'm on my third Holley trying to fix a problem of getting way to much gas into the engine. I've had three mechanics work on the engine but within weeks the problem returns. I got the engine with a 750 cfm on it. The first mechanics advice was to replace the high rise manifold with a low profile torker, replace the card with a Holley 390 and upgrade the ignition system. After the problem returned the next mechanic adjusted the float. After days the problem came back. The next mechanic said the card was WAY TO SMALL and I needed one around 650. So third card Holley 650 is on and a week later the problem is back. I cranked the mixture down to where the thing barely runs and it still floods the engine.

After reading the other posts ... it really the Holley Carbs? I have to admit the engine backfires when the flooding gets bad, through the card and exhaust after turning it off.

The engine is a 73 327 w/ good intake, headers and a high output ignition system. I'm about ready to give up and get a crate fuel injected engine even if it causes a divorce.... Ideas?

Reply to
Chuck Edge
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Obvious things that can cause this are, any foreign substance in the fuel that can get in the main float jet and keep it from seating fully and controlling the fuel pressure, also what fuel pressure are you running, is it a stock mechanical fuel pump or are you running an electrical pump? You don't need more than about three and an half pounds of pressure (static pressure) to run a stock engine, that will allow for flow at high rpm, if you are running a modified engine at higher rpms you may need more pressure. The objective is that there is always a sufficient amount of pressure to keep the fuel flowing even at high demand rates, ie...high rpm with full throttle application.

Check the inline filter, make sure it is good, and check the pressure. Too much pressure will overpower even the best float and needle and seat setup.

I've run many a Holley, on stock engines and on highly modded engines, street apps and strip. Never had a problem, I love Holleys, but yet I must admit, injection is very very nice.

Reply to
George

Unless you have a VERY healthy 327 a 650 is more than enough carb. High rise manifold will cost you some torque on the bottom end. Sounds like your flooding problem is not really in the carb if all three carbs had problems. I would check your fuel pressure. You shouldn't need over about 6 PSI unless you drag race regularly. Are you running a regulator? Run a good filter in case the problem is rust/crud from the tank.

Reply to
Steve W.
6 PSI? I think I remember 12 to 15 PSI showing up on the fule pressure gage when I first start shooting the problem. It has a mechanical pump but the pressure sounds like the problem. The filter is new and clean so let me double check the pressure. Can it be this simple? Thanks ... Chuck
Reply to
Chuck Edge
6 PSI? I think I remember 12 to 15 PSI showing up on the fuel pressure gage when I first start shooting the problem. It has a mechanical pump but the pressure sounds like the problem. The filter is new and clean so let me double check the pressure. Can it be this simple? Thanks ... Chuck
Reply to
Chuck Edge

I put a gage on the fuel line again and it jumps between 0 and 10 psi. Therefore I replaced the mechanical fuel pump and the needle only jumped between 5-6 psi. The flooding problem has quit! Hooray! After driving for a couple of hours I noticed that the fuel pressure gage is jumping between 0 and 10 psi again???????? It still is not flooding but shouldn't the gage stay steady within1 psi or so?

Reply to
Chuck Edge

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