Mikey Hawks

Happy Father's Day to all.

I need some advise. Just started driving my '64 convertible, body off resto a couple weeks ago and have some issues. When driving at low RPM, like when turning a corner, once I hit the gas the carburetor pops, the car bucks then drive off. I also get popping thru the exhaust. Had the carb off to be checked and all was good. Had the dizzy out since I had some floppiness in the weights. That was repaired and re-curved. Still have the same problem. Now I'm looking into the vacuum.






1. Below picture says to me 'manifold vacuum' by the 2 holes. Am I correct?



2. It appears the gasket and riser don't allow vacuum to enter the carb. The carb is a Carter AFB. Something doesn't look right to me. Are all these parts compatible with each other or does something need to be changed? Thanks for the help.

427Hotrod

Those holes allow exhaust to circulate and warm up the carb in cold weather. I never like having them...Vette's are warm enough under the hood and most folks don't drive in the snow much anymore with them. They certainly don't help with carb temps and today's gas which is designed to be under pressure (EFI) more than it used to be sitting in a carb and having a fuel pump apply vacuum to it (lowering boiling point).

Either way, the definitely need to be sealed by gaskets that don't allow the exhaust to enter the airstream of the carb. Think of it as an EGR system working all the time.

Otherwise...popping through both intake AND exhaust all the time could be poor valve adjustment, rockers broken, exhaust leaks allowing air to enter, poor timing and any number of things. Need some more info to help diagnose.

If it just does it while turning and then accelerating I'd look for water/trash inside carb bowl or a wiring issue causing electrical issues when turning. Again...would need more info on symptom to help narrow it down between carb or electrical.

JIM

Mikey Hawks

Thanks Jim. I thought of the valves as well and that's was next on my list. Timing is good, especially after the dizzy curve. I'm going to loosen all the valve and let them sit over night until the lifter springs loosen up, then re adjust them all.