fuel line questions

The SS braided hose is $3.60-$5.00 per foot plus fittings. Possible hose sizes are -6 (3/8"), and -8 (1/2").

http://www.amazonhose.com/default.asp for hose, fittings and complete hose assemblies

See http://www.aircraftspruce.com/catalog/mepages/alumtube_2024.php for aluminum fuel line tubing.

The 37 degree flare is the same flare angle as the AN fittings. Slide the flare nut, and then the flare cup on the line and flare away. Don't try to cheat and use a 45* automotive flare tool, you'll get leaks.

Any shop that makes hydraulic lines can flare the tubing and provide the fittings for a small price if you don't have access to the proper tools. Any industrial supply store will have a 37 degree flaring tool for sale. They tend to be somewhat expensive - $75 or more
http://www.mcmaster.com/ctlg/DisplC...319476238962&ScreenWidth=800&McMMainWidth=588

or
http://www1.mscdirect.com/CGI/NNPDF...H&PMT4NO=6174876&PMITEM=74787516&PMT4TP=*LTIP

1/4" ID is plenty large enough for 500 bhp. You won't be experiencing any performance losses as long as you have a pump which has adequate volume/pressure ratings for your setup. The lines are basically a moot point until you get to the point of limiting the volume for high power ranges.

You don't necessarily have to increase your pump simply because you get larger supply lines. Think of your fuel system as a water hose sticking out the side of your house. If you open the *****et half-way, you might get 5 gal/hr which we'll equate to a stock fuel pump. Let's say your injectors require 4 gal/hr at 80%. By simply replacing the hose with a larger diameter line will not change the needs of the injectors, they still need 4 gal/hr and are receiving 5 gal/hr.

Where people get into problems is by having too SMALL supply lines. The pump is capable of providing 5 gal/hr at our required pressure and the injectors only require 4 gal/hr but the tiny tube can only provide 3 gal/hr. Therefore, as long as the pump you currently have is capable of providing enough fuel for your needs you won't have to get a new one.

A n/a 500 bhp engine should require injectors somewhere in the realm of 35 lbs/hr @ 80%. At that rate, you're looking at peak volume to be 35 gal/hr (130 lph). So you'll need to get yourself a pump which will flow at least 35 gal/hr at the pressure you intend you run. Don't forget that pump volume decreases as pressure increases.

Beyond that, it doesn't matter what type of fuel line you use. If you go with solid lines, don't forget to periodically include rubber fittings to allow for vibrations.