Fuel sending unit question

[RodJohn]

Like to get some advice…. Wish I had more experience here.

Going to run a 383 stroker with a Holley Sniper EFI. Spoke to Holley and their recommendation is to run all 3/8” fuel lines (supply and return). I did. Now looking at return on the sending unit and it is a 1/4 inch pipe on the sending unit. Seemed to be a “restriction”. Holley recommended to change it to 3/8” pipe and suggested the return tube should go down to about 1” from the bottom of the sending unit towards the bottom of the tank. The 1/4 inch return pipe in the sending unit extends about 3/4 inch below the top of the sending unit so it would have to be extended 6 plus inches.

So, here are my questions…

1- Is this a concern and has anyone run into problems with the 1/4 inch return on the sending unit for a 383 / sniper EFI configuration when rest is 3/8” fuel lines?
2- Anyone do anything to increase volume on the return pipe of the sending unit and if so what did you do? E.G. drill out 1/4 tube and weld in 3/8”?
3- Do you need to extend the return deeper into the tank regardless the configuration and if so what did you all do?

Hopefully I am just thinking about it too much ;-)

Thanks in advance all.
John

[wrp]

I have the exact configuration 383/Sniper but I went 3/8 all the way, I used a Boyd Aftermarket tank. The advice about the return location low in the tank is spot on, that will avoid cavitation. JMHO

[gbranham]

I replaced the Roadster kit-supplied fuel pump hanger with the Pro-M 87-93 Mustang Race hanger. It has 3/8" feed and 3/8" return fittings, both -6AN. It also has a return extension, to ensure return fuel doesn't cause cavitation.
High Flow Fuel Pump Hanger for 1986 – 1997 Mustangs (promracing.com) (https://www.promracing.com/high-flow-fuel-pump-hanger-for-1986-1997-mustangs.html)

[RodJohn]

Appreciate the info…thanks!
John

[RodJohn]

Great videos with the link! Thanks for the info!

[gbranham]

You bet. Happy to help.

[MPTech]

x2 Greg's suggestion on the Pro-M Hanger. All your problems resolved and keep your existing fuel tank.
I'm running a fresh 347 build with Sniper EFI all 3/8".

[RodJohn]

Thanks!