[rpmerf]

Some questions that come to mind that might help figure out whats going on.

Was everything fine before you checked the compression?

What do you have your timing set at? Base, all in, all in RPM, vacuum. Manifold or ported vacuum?

When you say hot, is the gauge pegged? My gauge reads about 3/4 with a 195 thermostat. Have you verified the temperature or the block / head using an infrared thermometer / temp gun?

How is the electric fuel pump run? Is it inline with the old mechanical pump, or did you bypass it? All new hoses? Did you check the sock and any other fuel filters? Did you verify the flow of the old mechanical pump, or the new electric one?

What carburetor do you have?

Points or HEI?

How did the plugs look when you pulled them?



It wounds like whatever it is, is getting worse. Coil, HEI module, and fuel pump are 3 things that tend to run fine cold, then get worse when the engine heats up when they are failing.

I've heard some aftermarket carburetors are sensitive to heat, but I don't know 2 and a half miles would be enough to do that.

Another thought is that you are running lean. The choke gets you rich enough to run fine, then when it comes off, you are too lean.

If the ignition is too far retarded, it will run better with the rich mixture, then worse with the proper mixture with the choke off. The rich mixture ignites faster. Retarded ignition is also said to lead to overheating.