650 speed demon help
 

Have a 355 chevy with a edelbrock performer package in it and vortec heads. I put on a 650 speed demon and the car has a bog when you hit the throttle for a second or 2 before it takes off. It is a vacume secondary carb should i go with a stiffer spring to slow down the secondaries.

Several possibilties:
Weak secondary spring
Timing
Acc pump linkage out of adjustment
Bad check (the diaphragm thingy) for the main acc pump.

Good luck!!

I had the same problem with my 650 holley carburetor, it was a matter of getting the jets right and the cam pump on the side of the carburetor adjusted right. Finally after many tries I finally got it right.

Re: 650 speed demon help
 

Nope. Secondaries aren't even opening yet, when your first hitting the throttle. Try a bigger squirter and check for any vacuum leaks.

650 demon help
 

I agree w/ dparker. Sounds like a similar situation we were having w/ the monte that I was telling you about. Except the factory distributor was the problem so he bought a new HEI dist. hooked up the vacuum advance and that cured it. Since he drives it everyday this was a good choice for his pocketbook. Kris

650 demon help
 

Did you get youre carb straight??? Kris

650 demon help
 

I guess he fixed it.

Kris