Recently purchased a 1971 Cutlass Supreme, with an upgraded 455 , not an SX.
Haven't had any experience with the car yet in the summer months yet...so my question is regarding set-ups to avoid Vapor Lock scenarios...using Ethanol gas.
I understand the options may vary between:
... using Non-ethanol gas
... adding an insulator riser between my Edelbrock 1407 carb and Edelbrock Olds 455 Performer intake manifold
...adding a fuel return line (not installed on original Cutlass Supreme 350)
...having the fuel return off of either a new fuel pump (with a return line), or off a bypass pressure regulator (which I would assume would be better than a deadhead regulator?)...by adding a new sender with return at tank

Any thoughts would be appreciated...seems like the preferable setup would be adding a new pressure gage-bypass regulator-filter between the pump and carb, and adding the fuel return line on the car...any suggestions and setup pics?.

 

I live in Phoenix where all we have is ethanol gas, and I have not had any issues during our 115+ summer temperatures. My fuel system is all factory - mechanical pump, single line with no return. I will point out that Phoenix has a unique fuel blend that no one else in the country uses, so that may factor into why I have never had issues with vapor lock.

 

Thanks Ken...not sure I will have any issues yet....its probably more of looking for more things to do to the car, in idle winter months!...I am well aware of the old adage...if it isn't broke, don't fix it!

 

While Indiana doesn’t get nearly has hot as Phoenix, it gets plenty warm here. I personally have never experienced vapor lock. What I have experienced is difficulty restarting the engine after a hot shutdown. The factory pumps with the return line solve that issue.

 

Which is a form of vapor lock during a hot soak. I had issues with my car in 100+ Bakersfield summers. The fix was a 3/4” phenolic carb spacer and a jeep fuel filter with a .040” return port. I hooked that up to the fuel vapor hard line and modified the vapor lines at the tank to work as a return line. It went from long cranks after a hot soak, to firing up in 3 to 4 seconds without touching the throttle after sitting all day in the heat.
just saying.