Do I need a return fuel line with a calibrated 454?

[Griz]

I just started a thread yesterday about the difficulty I was having routing all the pre bent fuel and brake lines down the passenger frame rail. The lines were already stripped out when I got the project so no idea what rout or mouting holes to use for which line. I've now decided to bend my own fuel line and was wondering do I really need a return fuel line for a carburated 454? If I can delete the return I would run an older 3 port valve for the duel tanks and simplify the mess on the frame rail. I've read a little about people having fuel line vapor lock issues without the return but a vented gas cap and possibly just a vent on the return tank fitting should be enough to prevent any possible vapor lock?
Thanks for your help.

 

[nvrenuf]

Will you be using an electric or mechanical fuel pump?

 

[Griz]

Was just planning ion a mechanical pump

 

[Ricko1966]

The return line is a definite benefit,it keeps the fuel constantly circulating,to eliminate vapor lock. GM used return line on carbureated engines for a reason.I use mine as a return line for a fuel pressure regulator. Also the return line keeps the fuel line from building pressure when parked hot,which blows the needle open,which overfills the bowl and you get an extended crank on hot start. As for vented gas cap,bad Idea, the vented cap vents right to the atmosphere,you lose a little fuel,but bigger is when it cools it draws in cool,moisture laden air into your tank,so now you have fuel contaminated with water vapor,the water condenses in the tank washes around the bottom of the tank. Now you have a rusty tank. And vapor lock isn't caused or cured by tank vent,vented cap or lack of either.