Bypass fuel pressure regulator systems

[JHeath]

Key word is..."former super stocker" ,but you are not a class racer, as usual, your opinion is irrelevent.

[1320racer]

says the guy who barely runs in the 10s

[Ed Wright]

1320 is correct. Won't hurt, but won't run any faster unless it had fuel supply issues before changing to the bypass set up. Adequate fuel in the bowls is all the carb cares about.

[Sean Marconette]

The advantage of a bypass regulator it does not dead head the pump, like a non-bypass. Fuel is moving thru the pump at a constant volume with a bypass. This allows fuel to cool the pump. Dead heading is a low flow/no flow condition.

If you have a low pressure/volume pump like a Holley blue pump, a bypass would not be a benefit to pump life. If you have a high pressure/volume pump that is capable of being used on a FI system, a bypass will extend the life of the pump, and not dead head it. Most of the time a race car is idling around the pits, a very short amount of time is the engine at WOT. The needle and seat are the governing factor in fluid volume and how much cooling effect on the pump in a carb application.

[1320racer]

the PE 4450 fuel pump/filter combo in my car has been there since it was built in 2004. It has always been dead headed until earlier this year without one issue.



Further, I sent it to John earlier this year for inspection, feeling guilty after running it for 12 seasons and he said there was nothing wrong with it. Again, the bypass won't do anything for the OP except lighter his wallet by ~ $200 but if it makes him feel better, get it.

[nhramnl]

Again, thanks to all. I'm running a Q-jet combination and spoke with John Rademacher about the bypass setup when I sent the car's Product Engineering pump back for a rebuild. John's contention is that because of the Q-jet's very small fuel bowl, the bypass system is critical, since it assures a consistent supply of fuel. I don't believe I had a problem before, so I'm not really expecting a major gain, but I was curious if any of you guys that installed the kit (even with a good performing existing system) saw anything.

[1320racer]

FYI, I ran a Q-Jet for many years atop my 600+HP at the time, 468 BBC, running as quick as high 10's with it in my 3900 lb. Chevelle. No PE pump, regulator or bypass. Ran a Malllory Comp 140 pump, filter and dead headed regulator and no issues what so ever.

[junior barns]

What if there is a by-pass at the pump? Is it still needed at the regulator?

[1320racer]

one has nothing to do with the other and neither are required. Ran Mallory pumps for years without a bypass and as part of a dead headed system.

[Sean Marconette]

I guess the fuel pump companies that make a bypass for a carb setup are just plain stupid then? The pumps that the motors are in fluid will last longer with a bypass regulator.