Hello
New member here. Are carburetor mustangs prone to vapor locking in high temps? I had a 63 galaxie (352 edelbrock 4bbl) that vapor locked really bad. I live in Colorado Springs at about 6000' above sea level. They put alcohol in the gas here and it tends to boil at high engine bay temps. What fixes are there? I've added fans and tried to wrap headers as a solution.
Thanks in advance.

 

Vapor lock occurs when gasoline within a closed system boils. This can begin at fairly low temperatures, but depends on the pressure too. Gasoline containing 15% ethanol will begin to boil around 120 degrees F, which is certainly possible under hood. That initial boiling is very slight and slow, however, and doesn't happen within fuel lines which contain 4-6 psi of pressure. Within the carburetor the gas awaiting use in the engine "sees" only atmospheric pressure after the inlet needle valve traps it in the fuel bowl, so boiling there is far more likely.

If it boils vigorously some will spill over into the intake manifold flooding the engine. This may stall a running engine, or make a stopped one difficult to start. If the engine continues to run, it will consume more fuel than usual, until fresh, cooler gas continues to enter the fuel bowl.

Fixes include placing an insulating block between the carburetor and it's mounting base, increasing engine idle speed, and use of a lower temperature engine coolant thermostat. Additional air may be ducted to the carburetor from the engine cooling fan.