Jerry 84
What type of carb are you running? Vacumn Secondaries or Double Pumper? Primary jets should be about 65-70 and secondary jets should be 72 to 76. Run these and check the plugs.
Have you checked the ignition timing and proper function of the distributor's advance?
Are you running fresh, properly gapped spark plugs, spiral core wires, and a fresh cap and rotor? Have you checked the coil for proper operation under load?
You need to ELIMINATE IGNITION problems before playing with carb settings.
Put a vacumn guage on the engine and check it at every 500 rpm writing down the readings. With no loading, the vacumn should be fairly high. If vacume pumps or stumbles then we have a leak somewhere. No amount of carb tuning can correct a vacumn leak. Holleys most often leak around the base gasket and the throttle shafts. You may need a new carb if the throttle shafts are shot.
You need to check the PVC valve and the line. If they are wrong, the car will never pull under acceleration.
You need to verify fuel delivery. First check the float level. Then consider using a 3/8 fuel line and a 110 gph pump with a regulator. This will provide bowl fill at WOT.
With a stock cam and 1.7 lifters I would try a 65 to a 68 primary and a 72 or 74 on the secondary. A bad power valve makes the car run like dog poop at idle, but it will run great under acceleration, so I do not think this is your problem.
You may be having fuel delivery problems. You should probably be using a 3/8 inch fuel line, a high performance fuel pump at the tank, and verify that your float levels are properly set. A 300+ horsepower engine will need at least a 75 gallon per hour pump. I prefer to use a 110 gph pump and a pressure regulator to maintain about 6-7 pounds of pressure. A stock fuel pump usually delivers between 40-50 gph. This is hurting your top end.
Hope this helps. Email me at
jim_howard_pdx@hotmail.com and I will be happy to help you through the checks. PVC check first, then check your vacumn levels and look for leaks. Distributor check comes next looking at initial advance and full advance. Freshen up the plugs-wires-cap-rotor. Then check your carb. I think your secondaries are opening too soon. If you have a double pumper you may need to go to a vacumn secondary. If using vacumn secondaries you should be using a purple, silver, or brown spring on the secondary diaphram. When all this is done, then we can fine tune with the jets.