Only have the car a few weeks and have not really jumped on it till today. On hwy or from a rolling start it goes ok But from a dead stop it starts out great but starts breaking up at 3000 rpm. It is a big block 402 w a 750 holley msd 6al ignition crane cam w roller rockers, any ideas Thanks in advance Ted:confused:

I'd like to answer your question because the same thing is happening to me. It's a small block 283 with a 750 Holley DP with a 292 cam (hydraulic lifters).
It ran fine a month ago but now it has the same symptoms you describe. I'm leaning towards a weak fuel pump? :confused:


1965 Malibu SS hdtp./4-speed
http://i215.photobucket.com/albums/cc309/MalibuSeaS/4speedcar.jpg

1965 Malibu SS conv./slip-n-slide PG
http://i215.photobucket.com/albums/cc309/MalibuSeaS/conv_01.jpg

What have you already checked? Total timing? Wires? Plugs? Vaccum leaks???????????

Will it wing past 3k in neutral without busting up?Trying to determine if it is fuel starved..weak secondary voltage or perhaps rev limited purposely for break in.

I changed the fuel pump and the symptoms disappeared. After reading further I found that this "NEW" gas dissolved the diaphragm slowly causing it to suck air instead of gas. :angry:

Only have the car a few weeks and have not really jumped on it till today. On hwy or from a rolling start it goes ok But from a dead stop it starts out great but starts breaking up at 3000 rpm. It is a big block 402 w a 750 holley msd 6al ignition crane cam w roller rockers, any ideas Thanks in advance Ted:confused:

same thing happened to me. ended up being spark plugs. i would check plugs and wires first before anything. it could be that your timing is off or a fuel problem also.

Problem fixed it was the revlimiter chip in bottom of box it was a 6000 Removed chip car runs fine . Why can such a simple thing drive you nuts:hurray:Thanks to everybody who were nice to try to help Ted