I recently bought a 71 chevelle with a new 355 in it. It's got a holley dominator 2 intake, edlebrock carb (i believe it's a 650), a little bit of a lumpy cam (i don't know the exact specs), mallory electronic ignition, and a TH350 tranny. My problem is the car dies much more than it should. Cold or warm, when you gun the motor, it either drops off to about 100 rpm, and it BARELY comes back to life if you floor it, or it just dies completly. This is only if you gun it from a dead stop. You don't even have to hold the gas, it does it if you just kinda tap it and let off really quick. A couple of friends think my carb is just running very rich, but i was wondering if anybody had any other ideas. could it be my fuel pump? another stupid question...where is the fuel pump located? i'd like to see if it's stock or not, but i don't know where it is...=\ kinda lame. One last thing...it seems odd, but i can't get the car to peel out. Granted, i don't have lsd or posi, but i should still be able to burn them a little bit. Power braking dosn't work at all, in fact once you let off the brakes it makes this really weird humming noise until you turn the car off, let it sit, and start it up again. Any help on any of these things would be very greatly appreciated. Thanks a lot guys.

<BLOCKQUOTE>quote:</font><HR>Originally posted by Odelay:
Power braking dosn't work at all, in fact once you let off the brakes it makes this really weird humming noise until you turn the car off, let it sit, and start it up again. <HR></BLOCKQUOTE>

This phenomena I've never seen or heard of before http://www.chevelles.com/forum/confused.gif The other stuff, sounds to me like the carb is completely out of adjustment and/or timing is also not correct. The only definitive answer I can give you is that your fuel pump is located on the front lower passenger side of the block and has a line that runs up and feeds the carb. You shoulda put the pedal to the floor when you were test driving the car to see what you were getting for your money http://www.chevelles.com/forum/biggrin.gif

Mike

Ditto's with Mike. 1st verify your timing is correct. Then start checking the carb. Make sure your accel. pump is working properly.

Odelay, one very good possibility that would cause both of these problems at the same time is a ruptured/defective power brake booster diaphragm. It will display the same symptoms of a large vacuum leak and cause all kinds of illogical things to happen. The diaphragm moves inside the booster housing and can seal when the brake pedal is at rest but cause vacuum-leak-type problems as it begins to travel. There is a plastic vacuum check-valve that the large vacuum hose attaches to on the front face of the booster housing. Get a new one. They're just way too cheap to replace to even bother with checking to see if yours is OK or not. After that, get it to make the humming noise if you can, and, while it's making the humming noise, clamp off the large vacuum hose to the check-valve with a large pair of pliers or vise-grips. Don't cut it in half, just clamp it enough to block the hose.
Does the 'humming' go away? Does it idle any better?
We'll need to know this stuff before we go left (to the carburetor) or right (to the power brake booster assembly).

Can't wait to find out so write back, eh?

Louie Hammel