I went to the track last the track last night and only ran a 13.6 at 97 miles. The problem I was having was that just before the end of the 1/4 mile ended I would shift from 2nd into 3rd where the rpms were at about 3500, as they got to 4000rpms the rpms would stop rising and the car would stop making power. I was never able to get past 100 miles. I have a 355 zz4 with a 770 holley carb, and hot cam, with the old 2.73. Any ideas of what colud be wrong?

 

Welcome aboard.

1st thing that comes to mind is fuel delivery. The bowls are going empty after shifting to 3rd.

What are you using for fuel pump/filter/etc.?

 

I think I have an edelbrock High performance pump w/ a stock filter. What do you suggest I do? Change them out?

 

What kind of "Edelbrock high performance pump?" Did the car originally come with EFI? If so, is the stock pump in the tank operating, or is it still in there and not hooked up?

I'm assuming that's what you've got, because the stock filter in a carbed car is in the carb, and you don't have the stock carb (and Holley requires you to have a filter other than the inlet screens they put in).

 

I had a similar problem this year. My float level in the secondary bowl was too low and the bowl emptied at high rpm.

The problem could also be any number of things. Weak valve springs come to mind but I'd search for a fuel problem first.

 

It sounds more like a fuel problem because when I from the vaccum port to manifold port on th carb the problem was not as bad. I dont have the pump in the tank hooked up and it was a TBI before. I checked the pump and its a holley, it just a regular one, and after that I have regular ol filter, but there always seems be to build some oil and gas gunk on top of the pump. Are you saying I need another filter other than the one I have going to the carb.

 

If the TBI pump is still in the tank and isn't powered, there's your problem. The mechanical pump (I assume that's what you mean, the one mounted on the engine) can't suck hard enough to overcome the restriction created by the old TBI electric in-tank pump. Either power up the in-tank (and you'll need a return-type regulator before the carb, too), or get it out of there.

By filter, I mean an in-line filter between the pump and carb.

 

If you still have the factory filter back by the tank in there, that could also be a problem.

 

I'm not sure if the old pump was taken out of the tank. I guess is I will have to drop the tank to find out, not unless there is and easier way to do it. Thanks for you help.

 

check to see if that inline filter just after the lines come out of the tank is still there .thats where my problems were when i changed over.i just put a piece of gas hose there.