ok, last night we had my car out and it would run up to like 6 grand not even trying....tonight we took the chevelle out and when you floor it, goes but not as fast and last night yet, there is NO MISFIRE AT ALL, does not studder or backfire, its like accelerating and like hitting a brick wall...it just stops then you shift and get back to 5 grand and bam, same thing...like the power goes from 400 to instantly 0....


i have a brand new proform hei, accel super coil, new plugs and wires, cap rotor, timing is at like 12* and the fuel system is a holley blue eletric pump set at about 7psi, on a 7/16 fuel line the whole way and a 750 4bbl holley.

we checked the fuel filter and its fine and the only other thing we checked is for full throttle....maybe the bracket bent from last night because i jumped in the car a put it to the floor and my buddy pressed on the thing on the carb and it opened about another 1/2" or slightly more, maybe 3/4 inch


my questions are, could another like 15% of throttle make it not get enough fuel or air? like the 4bbl not opening enough>? he said something about not 0 vaccuum...and finally, what else could it be?

do you have a rev limiter?

Do you have a way to check fuel pressure at 5000rpm? Do you have another distributor to try? Could be a bad HEI module.

My first guess is a fuel thing.

Steve

Restrictive exhaust??

Do you have valve train that'll go to 6K with no problem? If nothing has changed between the two nights of running, I'd look first to see if it's a fuel problem, and then I'd carefully listen to the valve train. Any new or different noises? Is oil pressure and flow good at all RPM? Also, you do need to have full opening of the throttle... even a small restriction in movement may not allow the secondaries to open fully. You should have essentially '0' inches vacuum at WOT. if not, check for restriction, either going in (intake) or going out (exhaust).
-Bill

Correct the throttle inkage adjustment and make sure it's secure and try it again. If it's still dead, check the timing.It sounds to me like the distributer may not be tight and it has retarded the timing. or the mechanical advance has stuck and will not advance.
Let us know what you find.