231 odd fire compression

Fuel delivery is fine. Have a glass fuel filter and it is full when Engine starts acting up. Total Advance is hovering in the 35 to 36 range when engine is revved.
Another symptom is backfiring through exhaust and carburetor once in awhile when revved.

 

Vapor lock is usually caused by a weak fuel pump and aggravated by a high heat source near the fuel line. An old time cure from flathead Ford days is to install a heat sink on the fuel line between the fuel pump and carburetor. The heat sink was usually several clothes pins clipped on the fuel line, sometimes aluminum foil was wrapped around the line to act as heat shield in addition to clothes pins.

 

You mad me laugh.. When I was young, every flat head ford in the area carried a small sack of cloths pins and a roll of foil.