I am currently running a Holley "Blue" #12-802-1 electric fuel pump with a Mallory #4309 bypass regulator with -6AN lines.I have had a few of these pumps go bad shortly after installed and want to come up with a better, fail safe fuel system.The car is 90% street & 10% strip so I want a more reliable fuel system as I only need a max effort system 10% of the time.I like the idea of a mechanical pump as it is a much cleaner, and IMO more reliable system and more than adequate 90% of the time I drive the car.Only problem I see is if the car gets faster/hooks better at the track I may need to step up to an electric pump to fight the g-forces on the fuel flow at launch.So after searching here (Damon) and elsewhere on the net I have read and like the idea of running both an electric and mechanical pump.

I am planning to run the Holley "Blue" I already have into a Carter mechanical pump.I would like to have the "Blue" electric pump on a toggle so I can manually turn it on and off as needed.That way I can drive on the street with just the mechanical and if I plan to get on it/go to the track I can turn on the electric pump to aid the mechanical.Would the Carter mechanical pump be able to pull fuel through the electric pump when it is off?Would I need to run a regulator for when I do have the electric pump on or will the mechanical act as the regulator in the system?Has anyone ever done this with an on/off switch?

 

The mechanical pump will regulate in that setup. I don't know if the mechanical pump is going to draw through a stalled electric all that well, though.

 

replace the blue pump or rebuild it holly also has a red pump that has its own regulator
I do not think the mechanical pump will do what you need it to withoutr removing the electric pump



later

and

GB

rk

 

Supposedly the different colored Holley pumps are all the same, the only difference between them is the bypass spring.

 

the red pump dose not need a regulator by design they run at the proper line presure. The blue pump runs at a higher line presure and requiers a regulator.I went through all this with the Holley techs 2 years ago for the 68 ss

later
and

GB

rk