Question on how to run fuel lines on Walbro dual pump setup..
 

Hey guys I'm in the middle of a single turbo conversion. I have all the parts already. Based on the amount of power I'm shotting for I'm going with a dual walbro pump setup. I have the Rx7store.net extreme fuel system with kg rails, 850 primaries, 1600cc secondaries, aeromotive fpr, fuel pressure gauge, all the lines and fittings and shit. I've done a fair amount of research on it, and have found a few different ways that people are running their lines. I want to know what you guys suggest, and any pictures you can include of how you've done it.

nothing?

Use a Y-block inside the tank to a -10 line. Do not run each pump to a fuel rail. Use the y-block to carry all the fuel from the two pumps thru a single -10 line to the fuel rail. Magna fuel sells a nice y-block on jegs.com...

Jay7...

Why not? This is what I do.............

^^^Yeah why not??? This is also what I have done....

Just for your info anytime you Y two pumps or lines you will cut the pumps flow output down to about 70%.

I'm using the magna-fuel y-block mentioned above and it works fine. Though of course, I don't see any problem running one pump to each fuel rail either.

I'm guessing that the reason being if one pump dies you're SOL and you won't know possibly until it's too late.

I run two Walbros "y'd" into a -8 to a setup from CJ Motorsports. It's a -8 inlet into the secondary and has a tap that "y's" out into the primary. Both then feed a -6 to the FPR with a -6 back. The lines are run behind the stock plastic cover on the chassis with a clamp here and there for extra support. It fits perfectly. I uset 10' of -8 with just enough slack. This is a single line from the Y out back right into the rail. The only very minor issue is clearance, but with stock motor mounts, it wouldn't be an issue with this setup.

As far as pump output, perhaps you may cut your rated output per pump, but you still gain more than you loose. Though, YMMV and to each their own. I'd say that both work well and for street use, either are proven to work.

I do have a strange issue, but it may be related to something else and not for this topic to be sure.

Good luck.

You don't want each pump going to each rail. What happens if one of those pumps fail? Detenation from no fuel is what will happen god forbid one of those pumps fail. Run both pumps on the same line so if anything were to happen liek that you won't hurt anything you'll still have plenty of fuel...

Jay7..

If you feed one pump to each rail and t at the regulator it will balance pressure and flow to each rail there for the pressure will be the same but the volume will drop on both setups if one pump fails. If i am wrong someone please let me know and try to explain as i would not want to mislead anyone!

how do you wire it? two relays? or just one that splits the power?

Quite the opposite. Your motor will NOT break from NO fuel, but it will break if it has fuel but not enough....
How many times have I launched the car on low fuel to have it fall on its face and then take off as if nothing happened.
Fuel pressure would drop completely and come back up!!!

How would you have plenty of fuel if one pump were to fail ?
Unless you're under ~400rwh....but then again, you would not know if one failed till higher hp level.

I would run individual fuel lines from each pump and feed each rail and have other end of rails meet at the regulator.

My .02 :-)
JD

Yep, i agree with john... I tee in the rail at the FPR. thus if i have a pump failure, the other will compensate.....I run two LEDs in dash from the pumps, using a logic of power supply. anytime my drain is over 15Amps the light is on... ie operating pump. anything lower will not light the led.

Also i use one 150 Amp relay and one 50 amp fuse.... if either had to fail the whole system will stop.... thus reducing my possibilities of single pump operation.

i have each pump per line with 1000 and 1680s. duty cycles at 15psi rarely exceed the 70% mark.... base pressure at 45psi.