Fuel sending unit/line size help

[DarkoNova]

So it looks like stock LS fuel line sizes are 3/8" feed and 5/16" return according to Google.

I was hoping to just buy a sending unit with two ports and just basically drop it in and be good to go. Problem is, I can only find sending units with a 1/4" return line.

Is that too small? Am I just going to have to add my own port for a return line?

[Schwartz Performance]

What exactly are you finding? Does it say 1/4” NPT?
It’s not clear what sending unit you’re looking at, what tank you have, and even what car you have unless it’s a Nova like your username lol.

-Dale

[CarlC]

Depending on what you're looking to do, the Gen5 Camaro SS (2010) typically can be made to fit, can be converted to 60psi constant, and only requires a single 3/8" line to the rail. No filters, external regulators, return lines, etc. are needed. A Gen5 SS module new is about $112 from Rockauto, or about 1/2 that used on many of the Camaro forums.

https://www.vaporworx.com/documentation/fuel-modules/
https://www.vaporworx.com/documentation/vaporworx-mechanical-systems/

[DarkoNova]

Sorry, lol.

69 Nova.

I searched for sending units with return lines and can only find them with 3/8" feed and 1/4" return.

I originally wanted to just use the C5 regulator so I wouldn't have to run a return line, but I figured it would be easier to just plumb a return line since the engine is already set up for it.

Thanks Carl, I'll look into the Camaro stuff.

[andrewb70]

When you say "sending unit" what do you actually mean? Some more details would be helpful.

Andrew

[DarkoNova]

The fuel sending unit.

I figured that would be the easiest way to plumb a return line, just get a sending unit with a built-in return line.

Aside from welding a sump onto the bottom of the tank or welding on a port for a return line, how else are you guys doing it?

I do like the idea of using a 5th gen Camaro module, but I'm not the best welder so I don't know how I'd go about modifying the tank to fit it.

Oh and if it makes a difference, the engine is an 07 L92.

[andrewb70]

Why not just get a Tanks Inc. tank?

[DarkoNova]

I already bought a Camaro tank to move the fillet neck up from behind the license plate to up between the taillights. I'd rather not have to buy another tank, lol.

[andrewb70]

I already bought a Camaro tank to move the fillet neck up from behind the license plate to up between the taillights. I'd rather not have to buy another tank, lol.

Then I would highly recommend going with the Vaporworks setup using the Gen5 Camaro SS pump and the modification to run it at a constant 58psi. This also eliminates the need for the Corvette filter/regulator and will eliminate any fuel starvation issues.

Andrew

[DarkoNova]

Actually I just went in the garage and checked out the Camaro tank. I think it IS a Tanks Inc unit. I remember buying it either here or on lateral-g. It's already got the drop section where the sending unit goes and it has another hole next to the sending unit hole.

I'm a bit confused about the 5th gen unit, though. Why do I need to modify it at all? Do 5th gens control the pump with PWM?

I have a Holley Terminator kit ordered, I'll have to see how that controls the fuel pump.

And then what about the fuel rails? Do I need new fuel rails since the engine has a return style setup?

[andrewb70]

The TerminatorX just turns the fuel pump on. Carl can answer in more detail about his modification to the Camaro fuel module.

When you do the wiring for the Holley, I also highly recommend adding a power distribution module under the hood. This will feed the high demand circuits under the hood. I also do Holley EFI tuning.

Andrew

[DarkoNova]

Oh, that's good to know!

I just looked at the engine and it's a return less system, so either way I need to modify something.

I'll wait for Carl to chime in, then.

[CarlC]

All Gen5/6, 2009+ CTS-V, GM trucks, etc. all use PWM to control the fuel pump/system pressure.

The regulator that is in the module is used only as a safety valve and cracks at 88psi. This is so that there are not two pressure regulation systems working at near the same pressure.

The C5 fuel filter/regulator is a return type and has a return. Every mechanical pressure regulation system has a return of some type.

Lots of info here: https://www.vaporworx.com/documentation/