Fuel plumbing for an FE

[Carnut427]

Originally Posted by Anthony

Dan,

as cross sectional area determines max flow capabilities, the cross sectional area of a circle is pie*r*r, or pie*d*d/4. So, if I have a 2" ID pipe, the cross sectional area would be 3.141 sq inches. If I have a pipe twice in diameter, 4 inches, then the cross sectional area is 12.564 sq inches, 4 X as much. Therefore a 6AN hose has a 3/8" ID, and a 12AN hose, twice the diameter, has a 3/4" ID, the 12AN hose has 4X the cross sectional area, more area for fluid to flow, and should flow about 4X as much as a single 6AN. So, it would take 4 6AN lines to flow about as much as a single 12AN line...

As I have found out many times, things are usually alot more complicated than what they appear to be in the first place.

I stand corrected. Although I was a machinist and not an engineer, I did some research once at work concerning flow in steel pipe, and found the same info you report, that when you double the size you quadruple the flow, although for some reason I thought it only applied to steel piple, where a 1" pipe is actually a nominal sizing, and didn't realize it applied to tubing or -AN sizes as well. Thanks for the info, I'll reconfigure the info in my memory bank. BTW, I also found that one 90* bend creates as much resistance as 8' of straight pipe. We were having problems getting enough oil flow in some machinery, causing premature bearing failures.
By the way, the car still runs great...going back to my original rule of thumb of one 3/8" fuel line will support 400 hp, my two 3/8" lines are still good for 800 hp, although, thanks to you, I'm beginning to have doubts about that too...

Dan