Walbro Pump Setup

[88SS-357]

Hey guys. I not putting together a GN but using some GN fuel system parts so I had a few questions I'm hoping can be answered.

I'm using a GN fuel tank and modifying the current sender (have a spare to combine with my current one) to put in dual 255lph Walbro pumps. I am going to run both pumps into a Y block (T fitting) and run one single line up the car. Each pump will be wired seperately using its own relay.

First, what size is the outlet on the Walbro pump? I have one installed now and 5/16" comes to mind. Doing the math, the cross-sectional area for the outlet (for 5/16") for one pump would be 0.077 sqin , and for two would be 0.153 sqin. Doing the math, I would need a single line with a cross-sectional area of at least this size. A -08an feed is just about 1/2, having a cross-sectional area of 0.196 sqin. Does my math sound right?

So do Walbro pumps have 5/16" outlets or 3/8"? If its 3/8s" a -10an line would be better.

Any opinions on whether Id be better with a -08an vs -10an or personal experience?

Thanks guys

 

[yullose]

I'd just use an external pump and be done with it.

Mine's quiet as a mouse.

 

[turbofabricator]

Hey guys. I not putting together a GN but using some GN fuel system parts so I had a few questions I'm hoping can be answered.

I'm using a GN fuel tank and modifying the current sender (have a spare to combine with my current one) to put in dual 255lph Walbro pumps. I am going to run both pumps into a Y block (T fitting) and run one single line up the car. Each pump will be wired seperately using its own relay.

First, what size is the outlet on the Walbro pump? I have one installed now and 5/16" comes to mind. Doing the math, the cross-sectional area for the outlet (for 5/16") for one pump would be 0.077 sqin , and for two would be 0.153 sqin. Doing the math, I would need a single line with a cross-sectional area of at least this size. A -08an feed is just about 1/2, having a cross-sectional area of 0.196 sqin. Does my math sound right?

So do Walbro pumps have 5/16" outlets or 3/8"? If its 3/8s" a -10an line would be better.

Any opinions on whether Id be better with a -08an vs -10an or personal experience?

Thanks guys

The outlet of the Walbro 340 is .310" (5/16). I am building a dual outlet sending unit, which sounds like what you are doing, too. I am using two 3/8" outlets. (A 3/8 fuel injection hose will clamp down over the 5/16 pump nipple fine). I'll then Tee them together after going through two Stock AC filters. Then into a single -8AN fuel line. A single -6AN line will support over 700 hp. A single -8AN will support well over 1,000 hp. A -6AN is more than most engines will ever make. There are a few guys using the stock GN fuel lines and running low tens and high nines. The stock fuel line necks down to .257" at every fitting. (both ends of the filter, frame to rubber hose and then at the fuel rail). So, a 1/4" fuel line is all we really have on a stock GN fuel system. The stock pressure regulator also necks down to a .174" diameter. At 60+ psi you can move ALOT of fuel through a -6AN hose (3/8") Here's how I am going to get fuel out of the tank, using two Walbro 340's. I am building a new/improved version righ now. I'll be done tonight.

 

[norbs]

I need the same set up using two external pumps, inisde you will have to extend the s/s tube to the bottom of the tank and place two fuel socks on.,instead of the 340 pumps. This would be a nice option to have when selling your kit.

 

[88SS-357]

That sounds like a nice setup...I did see your setup when I searched. Do you have any pics of how the pumps attach? I'm planning on putting the Y block in the tank so I only have one -08an line coming out. If there is enough room I'll do it that way anyway.

Please post up some more pics if you can, would help a lot.

 

[Dean]

I am building a new/improved version righ now. I'll be done tonight.

A bit off-topic, but I've seen several of your posts. Do you sell any of your work?