running rough

351 Windsor in a '70 Fastback. Runs strong on acceleration all the way to 3000 rpm's then starts to cough and pop. The timing has been an issue before but think I'm right on the money now. Still cannot drop the hammer and turn it lose without it puking out and coughing. Seems to be missing. The firing order is right and there's no vacuum issues. It's got a brand new 600 CFM Edelbrock on it which has been adjusted a little but certainly not the problem. Any ideas?

Take the carb apart and reverse-blow out the secondary fuel circut's.

You're running lean after 3,000 rpm's...

What is fuel pressure at the higher RPM range now? It may be good at idle or low RPM, but when you really need to get pumping the big waster of fuel is coming up short then. Problem is that most of us can only check the situation while parked on the slab at idle. I found a gauge and line small enough to run up past teh hood gap, the centered near the outside to the windshiled so that I could read it. Up, down, up, down. When pressure got to near zero (past 2500 RPM) the performance esentially fell off.

The popping may be from fuel starvation. Look at any inline fuel filter, the line to tank, and the screen around the end of pick up too. Boy, that later one caught me for like a full year. Tank up and poop out ten miles down the road from the station. The new fuel would mix up the settlement in bottom of tank. Was getting dangerous to pull into such a place. Had tools ready to fix though.

You may be blaming something all wrong.


Wm.