Copper fuel line

[ak1234]

AK1131 .. just to aid you in your project the existing fuel line is 1/4 id / 3/8 od and you looking to upgrade to 1/2 od ?  This shouldnt be too hard especially if you continue using copper tube.  1/2 od is refrigeration tubing and soft enough to pull thru the path you require.
   
   Ron

[shep]

Where to start? On our race Cobra producing 500 bhp we would return 6 mpg at full racing speeds where the throttle was fully open for the majority of the time. Average speed for a lap was about 80 mph, depending on the circuit. At 80 mph  and 5 mpg we would burn 16 gallons per hour. In old units that is about 128 pints (64 quarts) per hour, or about 2 pints (1 quart) per minute. Even for 5/16" fuel line that is not a lot. We used 3/8" to be on the safe side, but also ran large bore fuel pressure regulators and fuel filter bodies. I am sure the Drag Racers can burn fuel much quicker than that, but they would be producing 800+ bhp. Answering your question, the 45 psi is not the flow rate, only the pressure pushing the fuel down the line. A Holley carb only wants to see about 5 psi, so 45 is major overkill. The pump requirement is 2 pints per minute or just over 1 litre per minute. A Holley red top fuel pump delivers 97 galls per hour at 7 psi or 12 pints per minute which is more than enough! They also have 3/8 NPT inlet and outlet connections so I would suggest going for 3/8 Aeroquip hose and fittings. Sorry for all the numbers and conversions, but that is how we worked it out for ourselves. Good luck, Andy.
   
   PS I am watching a CCTV monitor of one of our mares who is about to foal, so I doubt I'll get much sleep tonight! See even racers have a life outside of cars!

[shep]

Damn, I just looked back at the start of your thread, and you are running EFI. From my pumping knowledge at work, as the pressure increases, the pipe diameter can decrease. If we agree on the flow required by the engine at a max of 2 pints per minute, then the 5/8" hose will be plenty big enough for low pressure pumps and even more comfortable at 45 psi. Sorry, I am so used to carbs I didn't spot the EFI bit, Andy.

[AK1131]

If the existing line can be removed from the box channel then I think we are going to replace it with high quality copper of a larger diameter. This will permit us to have a fare & fitting to connect to the braided fuel line. Any comments or suggestion on a use of a copper fuel line?