fuel line size for 506hp?

[sbenso]

418w (506hp) with Mass Flo fuel injection, primarily street driven

I cannot get a definite answer for fuel line size, 3/8" or 1/2" size? I know 1/2" would be the safe way to go, but would 3/8" suffice? I am not interested in Mass Flo fuel line/pump kit. what are your thoughts? thanks

shawn

[vettestr]

#6 or 3/8" is plenty.

[blykins]

-6 to -8AN

[RodgerH]

Depends on the system you choose. With the pump at the tank, you may want to use a bypass regulator at the engine and -8AN supply and -6AN return.

http://www.aeromotiveinc.com/d_syste...temdisplay=efi

Rodger

[Murphy]

The kit is not a bad deal once you add up what you will need to piecemeal the system. To answer your question the instructions with the kit were to use an 8AN from the tank to the pump. 8AN from the pump to the filter. 8AN from the filter to the rail. 6AN from the rail to the pressure regulator. 6AN from the regulator back to the tank. The Mallory external fuel pump that Mass Flo provides has a port for fuel pickup with a T in the return line. You can see a picture of my fuel pump in my gallery. Good luck.

[sbenso]

I have a Walbro 255L/hr in-tank pump that I was intending on using with the -06 to the rails and return.

shawn

[BDR 699]

I just bought the Mass Flo kit and will be installing it this weekend. It came with an Accell pump (looks just like the Mallory, and uses the same repair kit part numbers). It also comes plumbed for 8AN only to the filter; from the filter to the rail (and beyond), it is plumbed for 6AN.

I bought fittings to upgrade to 8AN from the filter to the rail. Had to get them elsewhere, as Mass Flo was not willing to do any substitutions.

My engine builder (Keith Kraft small bolock 427) recommended 8AN to the rails, rather than 6AN. He also recommend the Mallory (Accell) fuel pumps much greater capacity than the Walbro. Chris at Mass Flo recommended the Walbro, with 6AN everywhere. I followed my engne builder's recommendation. I did not want any questions down the road if I was to have an issue.

[Ronbo]

I had ordered the kit but even though Chris said #6 would be fine (634hp) every other source said #8. So I am going with a larger pump. You have to assume there will be some degridation in flow as the pump wears and the filter starts to clog.

Also use the same size return / feed, under idle conditions you'll be sending most of the fuel right back to the tank. Under high vacuum the regulator is designed to lower the pressure to 40psi so you don't want any restriction in the return.

Basically, having larger lines won't hurt. The price difference is not very much. I'm also running a y-block with two #6 lines into the rails and two #6 lines to the Reg. This will help keep the pressure equal across the rails.

Might be overkill, but so is everthing else about the car.