Fuel Sending Unit with 1/2" Pickup and 1/2" Return Lines

[BLAM]

I was wondering if anyone has come across a fuel sending unit for a 68 Charger that incorporates 1/2" lines for both the pickup and return.

It will fuel my 512" Solid Roller motor.

If I have to I will modify a 1/2" sending unit to include a 1/2" return but was hoping I could just buy a unit ready made.

Thanks for the help.

Andy

[Ghoste]

I don't recall ever hearing about one with a 1/2 inch return.  I do seem to remember somebody selling 1/2 inch sending units but not the other half.

[motorcitydak]

On musclecar TV on spkie when they built the project Overkill Challenger with that 528 Hemi they used 1/2 inch feed line and a 3/8 return. I do not think you really need a 1/2 return line since that 512 will be eating most the fuel that gets sent to it anyway

[BLAM]

Yeah I was thinking 3/8" return would be fine but Aeromotive (my pump supplier) highly suggests the 1/2" return.

[Rolling_Thunder]

Yeah I was thinking 3/8" return would be fine but Aeromotive (my pump supplier) highly suggests the 1/2" return.

3/8" is fine...    hell even their regulators use a -6AN return   (-6AN = 3/8")

[BLAM]

The A1000 pump has a regulator with a 10AN line in and a 8AN line out with 6AN lines going to the carb.  The A1000 moves 900 lbs/hr at 8 PSI.  Tech guys says at that kind of volume you want the added capacity of the 1/2" return.

Thanks for the input guys.  As always there is great help from the members of this forum.

Now I just got to take all the data and figure out what to do.

[oldschool]

The A1000 pump has a regulator with a 10AN line in and a 8AN line out with 6AN lines going to the carb.  The A1000 moves 900 lbs/hr at 8 PSI.  Tech guys says at that kind of volume you want the added capacity of the 1/2" return.

Thanks for the input guys.  As always there is great help from the members of this forum.

Now I just got to take all the data and figure out what to do.

thats the exact setup i run.on one car it makes 870 hp.it could probably could support more......

[firefighter3931]

Andy, the return line needs to be the same size (or larger) than the supply line. I'm in the same boat and will be welding a 1/2in bung on the corner of the fuel tank to use as a return port. 

You need adequate return volume to keep the pump cool and the fuel circulating adequately....too small of a return line will induce pressure creep. At idle and low speed operation most of the fuel will be returning back to the tank. Even at WOT you won't be using anywhere near 900lbs per hour.


Ron

[BLAM]

Hi Ron and thanks for the info. Yeah that was exactly what the Aeromotive Tech was getting at in his discussion with me.  He made it clear that low RPM operation the pump will flow more fuel than the 3/8" line can handle and result in pressure build up and reduced life of the pump.

[kamkuda]

Definitely The return needs to be at least the same size as the feed line. 

I have heard of people plumbing the return into the filler tube that goes to the gas tank.  You will want to be careful of aeration of the fuel in the tank so be careful of the position.

[MoparSam]

So what would be the problem with just plugging the return line at the sending unit if your just going to have steel braided 6 AN line with a Holley blue electric pump all the way to the carb (like I've done)   

[mopar_nut_440_6]

So what would be the problem with just plugging the return line at the sending unit if your just going to have steel braided 6 AN line with a Holley blue electric pump all the way to the carb (like I've done)   

I have burned out two Holley blue pumps because I had no return line. Holley recommends a return to cool the pump and allow fuel to return to the tank so your pump has somewhere to bleed pressure.

[Grip64]

So what would be the problem with just plugging the return line at the sending unit if your just going to have steel braided 6 AN line with a Holley blue electric pump all the way to the carb (like I've done)   

I have burned out two Holley blue pumps because I had no return line. Holley recommends a return to cool the pump and allow fuel to return to the tank so your pump has somewhere to bleed pressure.

This is correct, but beware if you run at the strip, shut of your return line first or you run the risk of leaning out the motor with fuel going back to the tank, when the motor needs it most !!!!!