Help Again?

chevy1977 · Nov 20, 2022

I have a 1977 chevy cheyenne 350 5.7 liter small block chevy. I've replaced the carb and plugs, wires, cap and rotor. And still runs rough in the mid 2 to 3,000 rpm range. Any thoughts?

fast 99 · Nov 21, 2022

There are almost endless possibilities. First thing I would do is check vacuum when the issue is occurring. That would eliminate many internal engine problems such as a broken valve spring.

Check distributor advances for proper operation and fuel pressure.

Should be HEI if so swap out the cap and coil assy. When doing that look very closely at the small wires where they attach to the pickup coil inside the dist. They sometimes break and cause intermittent ignition problems when the vacuum advance turns the plate.

Help Again?

chevy1977

Junior Member

fast 99

Full Access Member

Similar threads

Latest posts

Forum statistics