bg400 question.........

[69firebird]

is there any advantage to blocking off the bypass at the pump and installing a bypass regulator on a fuel distribution log up front? i currently have the bypass at the pump and 2 mallory 4207 regulators on a fuel log up front. any suggestions,ideas, critics, etc? 1 regulator is for the carb, the other is for a big shot plate system that i have not used yet. any helpful info is appreciated
thanks in advance

[John_Heard]

From what I've seen with the bypass at the pump you will see a drop in pressure at launch that will recover as the G-forces drop off - that is with a rear mounted cell. Think about it you've got that long column of fuel that the pump is trying to push forward and when gravity doubles it has to have an effect.

With the bypass regulator mounted up front and a return line you now have a long column of fuel returning to the cell which seems to counter act the forces at launch. From what I've seen on my data logger this does work and gets rid of the dip in pressure at launch. Mine runs very flat during a pass. I would highly recommend APD's bypass regulator to mount up front, it's low cost $89? and works perfectly. You may have to shim the spring in it to get the pressure you want though.

[TubbedTruck67]

I run an A2000 pump with a bypass regulator up front on a log and it works very well. I would recomend doing it that way.

[69firebird]

by taking the bypass off of the pump assembly, will this put excessive load on the pump considering the amount of fuel the pump has to push at 25+ psi during launch??

[John_Heard]

You would still have a bypass up front, and the theory - mine anyway, is that the return line is counter balancing that force at launch with it's column of fuel returning to the cell. No, I don't think you'll see any increased wear/tear on the pump doing this.