Fuel Injection

[Randy]

Has any body used the new Holley Sniper fuel injection master kit yet. Only four wires to set up and no need for a return line if you use a specific fuel pump with the kit, just wondering?

 

[Don Jacks]

Randy,The problem with the one line system[no return line] is that it's harder on fuel pumps.They don't like to be "deadheaded" when you're dealing with the pressures that are needed[50-60 psi].Carl McQuillian told me that the new Holley ecm's learn really fast. Heretofore it took nearly 400 miles for them to fully learn.He said that the new ones come in in about an hour.

 

[Clint]

Randy,The problem with the one line system[no return line] is that it's harder on fuel pumps.They don't like to be "deadheaded" when you're dealing with the pressures that are needed[50-60 psi].Carl McQuillian told me that the new Holley ecm's learn really fast. Heretofore it took nearly 400 miles for them to fully learn.He said that the new ones come in in about an hour.

They use a special filter that has a return line that goes back to the tank.

 

[jdk971]

corvettes use one line and a filter at the tank. the filter does something that cuts the need for a return. when i had a ls3
put in my vette they used that filter. jim

 

[Randy]

In regards to the return line, Holley said that, a return line is an option but in an older car, like mine with stock tank, wouldn't that involve getting a new gas tank with a return nozzle/inlet ? If it's not one thing it's another.

 

[Phil Reed]

No....get a 409 gas tank sending unit and it already has the return line fitting!!!

 

[Don Jacks]

Either what Phil said,OR just put the return fitting in the filler neck where it goes into the tank.No need to mess with the tank. If you were making a bunch of power,the stock 5/16 fuel line would be used as a return line and a new bigger line installed[3/8 min.].On your little engine that wouldn't be necessary though.

 

[fourzeronine]

Holley does have a "drop in" retro-fit fuel pump module that is internally regulated and doesn't require a return line.

corvettes use one line and a filter at the tank. the filter does something that cuts the need for a return. when i had a ls3
put in my vette they used that filter. jim

The C5/C6 fuel filter (pictured) that's commonly used in LSx swaps includes a regulator and return line output. Two lines run between the tank and the filter (supply and return). It regulates to 58 psi.

Other GM models use fuel pump modules that are internally regulated and don't utilize a return line.

 

[Randy]

If I read the info on the Holley Sniper fuel injection correctly, there is a built in regulator on the system at the injectors, that is how they can incorporate a one line system I think.

 

[Don Jacks]

Yes,but that doesn't solve the dead head issues long term.If you do go that way,be sure to replace ALL rubber hoses from the tank forward.The factory had at least one or two connections in the fuel line going forward and they likely won't take the required 58.5 psi that the system needs to operate as designed.