ajr2820

I bought a fuel pump with the return line. The original was without one. I am doing a frame off and can simply run a return line and since I am replacing the tank as well, get the corresponding tank. One question though. Is there any advantage or disadvantage to this?

joe_padavano

I think fuel return is second only to Transmission Controlled Spark in the number of questions it generates.

The whole point of fuel return is that it recirculates part of the hot underhood fuel back to the tank for cooling. This was done to help mitigate percolation and vapor lock. This is why it was primarily used on cars that would be hotter underhood, mainly A/C cars and performance models like W-cars. Given today's crappy, ethanol-laced fuel, there's even more reason to use fuel return. Alternately, you can also just cap the extra port on the pump. Or, get the right pump for your car.

matt69olds

The fuel pumps with return lines were used on cars with air conditioning. The purpose is to constantly circulate a small amount of fuel back to the tank to help keep the fuel and pump cool. The added underhood heat from the A/C could cause vapor lock issues. The other advantage is preventing the fuel from boiling and raising the fuel pressure enough to push the needle off the seat in the carb. That helps hot restart and flooding issues.

With the crappy gas we have to deal with, I’d run a return style pump.