Fuel Line Size

Posted By: CHRGR69

Fuel Line Size - 07/10/09 05:00 PM

71 Cuda 383 Eddy 750. I have a new fuel pick-up/sending unit that is 5/16". I'm told I should go with the 3/8" line. Will it work with the 5/16" unit, or am I defeating the purpose of the larger line? Should I change unit and go 3/8"??

Posted By: Andrewh

Re: Fuel Line Size - 07/10/09 05:13 PM

kind of a waste. I was told the feed from the tank was most important. That is I started with a 3/8 pickup and went to 5/16th line after the electric pump.

Posted By: CHRGR69

Re: Fuel Line Size - 07/10/09 05:29 PM

Quote:

kind of a waste. I was told the feed from the tank was most important. That is I started with a 3/8 pickup and went to 5/16th line after the electric pump.

I'm using a mechanical pump.

Posted By: 64Post

Re: Fuel Line Size - 07/10/09 05:47 PM

Paging Crizila... Paging Crizila...

Posted By: Crizila

Re: Fuel Line Size - 07/10/09 10:28 PM

Quote:

Paging Crizila... Paging Crizila...

Your too funny Dave!! Thanks for the laugh

Suggest you go to a 3/8" tank pick up. I couldn't buy one for my particular application, so I modifyed mine. Easy to do. Just take your existing sender, cut off the 5/16" line on both sides of the bung. Drill it out to 3/8" and solder in you new 3/8" line, duplicating the length and bend of the original line. If you are going to stick with 5/16" at the tank, no sence in going to a 3/8" line. It's gotta be 3/8" all the way if you want to benefit from a bigger line. If you are running a whimpy little street hemi, you can probably get away with the smaller line. BTW, there are some guys on this forum that can make over 600 HP with a 5/16" line - - - they said.

Posted By: 64Post

Re: Fuel Line Size - 07/11/09 07:48 AM

Quote:

BTW, there are some guys on this forum that can make over 600 HP with a 5/16" line - - - they said.

John, if I didn't know better I'd think this was directed at me.

But then again, how would you know my tubing is undersized?

Posted By: Crizila

Re: Fuel Line Size - 07/11/09 04:17 PM

Quote:

Quote:

BTW, there are some guys on this forum that can make over 600 HP with a 5/16" line - - - they said.

John, if I didn't know better I'd think this was directed at me. But then again, how would you know my tubing is undersized?

It surely ( and don't call me Shirley!) wasn't Dave. All I can remember from those previous posts is that somebody made that statement. There are a lot of very sharp guys that frequent this forum, and I'm sure who ever said it has probably done it - - -

Posted By: thebankerstoy

Re: Fuel Line Size - 07/11/09 05:24 PM

I've always respected the fact that Chrysler used 5/16" fuel lines on low output big block cars and 3/8" on Hemi's and high output big block Wedge cars.

I have a mildly modified 440 in my 66 Coronet 500 that puts out around 400 hp and I run a 3/8" pick-up tube and fuel line all the way up to the carb. For the fuel pump, I run one of the Mopar Performance hi-performance mechanical pumps.(part #P4007039AB) To keep the fuel clean, I have one of the Fram HP1 canister style fuel filters back by the stock reproduction fuel tank and a 3/8" in-line filter up front between the fuel pump and the Holley 750 cfm vacuum secondary carb. I've had zero problems with this set-up for many years.

Richard