I put on a performer 600CFM on a 1977 stock 460 to replace the rebuilt stock Holley that was leaking every where. The truck won't start and it seems to be flooding. My questions are: Is the stock fuel pressure to high?
Do I need a special adapter to use this carb?

Any help to get this truck running is appreciated!

 

When we put a Edelbrock 750 on our 87 460 we had to use a Summit racing fuel psi regulator set at 6.0 psi to prevent fuel from coming out the top and sides.

 

You should be just fine with the stock fuel pressure. Something else is wrong. Is the Performer carb new or used?

If you want to look down the carb to see what is going on while it is cranking, use a large inspection mirror and a flashlight - you don't want to have your head over the carb! See if fuel is dumping into the throttle bores when you are cranking. You may have a bad float or stuck-open needle valve, or the float setting could be too low.

Try disconnecting the fuel line from the carb, plugging it (a 3/8" bolt and a hose clamp will work), and seeing if you can get the engine to fire on starting fluid. That will tell you if everything else is OK.

I understand what the above poster said about using a regulator, but the stock fuel pressure is around 7psi, so if it was OK to start with, lowering it 1psi wouldn't have made any difference at all. Maybe in their case the fuel pump was defective or a higher-pressure electric pump was being used.

 

From the Edelbrock Q&A;

"Q: My carburetor is flooding, what do I check?

A: Carburetor flooding can be cause by the following conditions. First, verify, with a fuel pressure gauge that the pressure does not exceed 6.5 psi. Floats should be set to the factory spec of 7/16, (see owners manual).
Needles & Seats can be clogged with debris, not allowing them to close. They can be cleaned and checked when the float level is being verified. Floats can be sinking due to a leak. Verify floats are free of any fluid by shaking the float, or submersing it in a safe, non flammable fluid. "

In my experience these carbs are very sensitive to fuel pressure and often need a regulator when used with a mechanical pump.
5-6 lbs is all you want, or need.

 

Thanks for the help. It was a new carb. I had a fuel regulator and it continued to flood the manifold so I went to another Advance auto and they swapped it out for a Holley 600CFM and she cranked right up! The crazy thing is the Holley was only $240 with a 10% military discount and it had the kickdown linkage, the performer was $307. Now one of my four dentsides run so I don't have to hear crap from neighbors and family!