What are you guys running for fuel lines with 600+whp on E85? Are you guys running the stock hard lines? I was thinking of having some 3/8" hard lines made as 5/16' on E85 seems to be pushing the limit for 600+ and potentially leaning out.

Thanks,
Anthony.

 

The factory lines will support 700whp+(there are many examples) on e85. I made 635whp with zero issue on the OEM feed and a Buschur double pump setup.

 

Alright that's what I needed to know. Thanks.

 

a 1/8" diameter line could also support 700 whp if enough pressure is put behind it. i measured ~15 psi of dynamic back pressure in the stock supply line at a lowly 500 whp worth of e85 flow. the back pressure increases as the 2nd or 3rd power with fuel flow. at 700 whp, the dynamic back pressure of the stock line is north of 30 psi. add boost pressure at peak power (usually 35+ psi on high hp builds) and base pressure (say standard 43 psi), and pressure at the pump is 105+ psi. all the available flow curves show that there isn't much isn't much flow coming out of any in-tank pump on the market at 105 psi.

there are a few band-aid solutions:

- lower base pressure to 33 psi. this gets pump pressure down to 95 psi which does help.

- run a way oversize injector (2000 cc/min), and tune around falling fuel pressure at the rail. this is probably how many people make 700 whp on the stock supply line.

eddie - if you are planning to use the stock supply line for your new build, i strongly suggest that you reconsider running at least a -6 AN teflon soft line or a -8 AN hard line (approx equiv ID). If i were doing a 700+ whp e85 build, i'd do -8 AN teflon for overkill.