View Full Version : fuel line sizing for 440 HP engine

04-07-2013, 01:00 PM
The original 400 CI engine was replaced in my 74 RR with a 75 440 HP engine. I need to replace the fuel tank so I'm thinking of replacing the sending unit as well. The outlet tube is currently 5/16" dia. My question is do I need to install a sending unit with a 3/8"dia. outlet tube as well as a new 3/8" fuel line?

04-08-2013, 04:12 AM
I say no, I have run 450 hp engines on stock 5/1 lines

Madman Stephan
04-08-2013, 09:20 AM
I would upgrade to 3/8" even though your current engine specs might not require that much fuel. At least, if you decide to beef-up the motor in the future, the fuel supply will be in place. Plus, can you really trust that 40 y.o. fuel line?

John Kunkel
04-08-2013, 05:50 PM
Lots of muscle Mopars that had 3/8" pickups in the tank only had 5/16" lines from the tank to the pump and carb.

04-09-2013, 01:31 PM
I would say 3/8 is not necessarily needed, but if you are replacing it anyway, I'd buy 3/8 tube