Should not require a return line unless you are considering using a bypass fuel pressure regulator if I understand your application correctly.....FWIW

 

Hi to all,

I have a 72 Chevelle and I'm going to run a carbed 383 stroker engine. The body is off the frame for the moment so I'm focussing on finishing up the brake and fuel lines. I'm using a 3/8'' fuel line. I was wondering If I have to use a return line and vapor line? The car that the 383 stroker was in before I bought it didn't run any return and vapor line. There is only 1 inlet and 1 outlet on the engine mechanical fuel pump. I'm also not planning to connect/use the canister located behind the back seat. Only the main fuel line from tank to pump and a vent on the fuel tank.

Will I be okay? The car is not a concourse restoration, only a good weekend driver.

Thank you very much!

I have 2 brand new 3/8 fuel lines from "Inline Tube" sitting in my garage because my body didn't come off. If yours is off now, you might consider running the vapor/return line now for possible use in the future. I never dreamed I would have EFI (which requires the return line) but I do now and I love it. My point is that it's a lot of work to pull a body off just to route a fuel/vapor line if it were ever needed. I had to run soft line which I didn't like doing but was assured by the manufacturer that it was safe and acceptable (Earl's VaporGuard from Holley). Just a thought.

 

you might consider running the vapor/return line now for possible use in the future. I never dreamed I would have EFI (which requires the return line) but I do now and I love it. My point is that it's a lot of work to pull a body off just to route a fuel/vapor line if it were ever needed.

X2

 

run the 1/2 lines for fuel now!.

 

Plan for future upgrades. Do it now while it’s easy. Half inch fuel line and a return line. For a vapor canister I used my old pre existing fuel line and hooked up to a Harley charcoal canister but it’s not necessary. You just need your fuel tank to be able to expand and contract. Cars that came from the factory with charcoal canisters used a 5/16 line up the driver side frame rail to the engine compartment if I’m not mistaken.

 

Thanks to all for the comments. The body is off the frame at the moment so I think I will add a fuel line for an eventual futur EFI swap. My main line is a 3/8'' and I still have enough leftover to add a "second" line. So, is 3/8'' OK for a return line?

 

yes, fine. I ran a carbon canister on my 70 because I couldn't stand fuel smell in the garage. the gas tank must be able to vent somehow, the canister let it vent and controlled the smell both. works for me.

 

If using the mechanical fuel pump, run two 3/8" lines from a sump at the tank to a tee in the fuel pump. Then run a 1/4" line from the supply to the carb back to the fuel tank.. That will keep the gasoline, cool and well mixed..