Fuel Lines- Need Help

1/4 is smaller than 5/16..... if you want bigger go with 3/8 or 1/2 or 7/16. your issue is not fuel pressure but volume. you will only flow as well as your smallest part. Go down to Advanced and get all sizes of fuel hose you can just run your own fuel lines in whatever size you want up to the rails. Just make sure the pressure from the pump cant blow the line off.. ( ask me how i know)

You will need to run some new fuel feed lines or braided hose. The 3/8" & 1/2" aluminum tubing works well, but you will need a flaring tool and bending springs to fabricate the lines. Braided hose is easy to run and route, but is much more expensive. It is about $3.50-$4.00 a foot plus the end fittings, which are $3-$4 each. Fabricating hose assembles can be difficult, but anyplace that makes hydraulic hoses can do it for you for an extra charge. See http://www.amazonhose.com for more information.

For some help fabricating your own stainless steel hose assemblies, see
http://www.turbinefun.com/Stainless_Braided_Hose_Assembly.asp

For stainless steel braided hose and fittings for automotive use:
See http://www.summitracing.com/search/?keyword=stainless steel hose&dds=1
http://www.summitracing.com/search/?keyword=stainless steel hose&dds=1

http://www.jegs.com/webapp/wcs/stor...hall&searchTerm=stainless+steel+hose&x=18&y=4

See 13. See [url] http://www.eaton.com/...rformanceProducts/FittingsProducts/index.htm for more information on High performance automotive hose productsl for more information on High performance automotive hose products

AN fittings require a 37 degree flaring tool. A standard automotive or household plumbing tool is 45 degrees and cannot be used with AN flare fittings. If you do, the flare is subjected to too much stress when the fitting is tightened, and is likely to fail or leak.

See http://www.mscdirect.com/ , http://www.mcmaster.com/ or for the flaring tool you will need . Prices start at $85 and go up

http://www1.mscdirect.com/CGI/N2DRVSH?PACACHE=000000013509163
View attachment 148619

http://www.mcmaster.com/#flaring-tools/=b4fxc3


Last time I was in Summit racing, they had a 37 degree flaring tool for less than $40. It may or may not be a catalog item.

Ur out of fuel? Or ur tune is not right? What psi at high rpm? Has your tuner done a true flow test? We only run 39 lb inj off a wlb 255 and an msd BAP on the 2004 mac. With dyno tested 455 hp na and 700 hp with NOS. We have never ran out of fuel. On that note we are now having issues with the psi dropping but sup the wlb 255 is going out. I have herd that with the forced induction a BAP is a must cause as manafold pressure increases the amount of vac going to the reg that controls the fuel pump decreases and slows down the pump. We had this issue with ours even with it being NA. The Bap fixed the issue. Also what is the duty cycle of your pumps set at?

What size feed and return did you wind up installing?

Your graphs are mostly unreadable.

To maintain rated fuel flow for injectors, you have to increase the fuel pressure 1 PSI of each PSI of boost.

Example: Injectors are rated at 60lb, at base fuel pressure of 40 PSI. You have 10 PSI boost. The effective fuel pressure is then 30 PSI. In order to get the same 60 lb fuel flow volume, you need to crank the fuel pressure up 10 PSI to 50 PSI.

See http://users.erols.com/srweiss/#jcalc for some calcultors to help you figure ou the injector size and flow rating.

http://users.erols.com/srweiss/calcpchg.htm