Fuel System Question

[Rory428]

The Red is 97 GPH, the blues are 110 GPH.  IMHO anything un-self regulated above 60 GPH should have a return regulator and line.  Regulator mounts AFTER the carbs, not before the carb feed(s).  If you're going to stick with using that jack hammer on the car.

How does one mount a fuel pump regulator AFTER the carbs? Seems to me that once the fuel finds its way into the carbs, pretty hard to do anything with it. As for "stick with using that jackhammer on the car", when I first installed the Holley pumps over 30 years ago, I installed it by following the instruction sheets that came with the pumps. Should I be expecting issues from doing so anytime soon, IYHO?

[cjshaker]

The Red is 97 GPH, the blues are 110 GPH.  IMHO anything un-self regulated above 60 GPH should have a return regulator and line.  Regulator mounts AFTER the carbs, not before the carb feed(s).  If you're going to stick with using that jack hammer on the car.

How does one mount a fuel pump regulator AFTER the carbs? Seems to me that once the fuel finds its way into the carbs, pretty hard to do anything with it. As for "stick with using that jackhammer on the car", when I first installed the Holley pumps over 30 years ago, I installed it by following the instruction sheets that came with the pumps. Should I be expecting issues from doing so anytime soon, IYHO?

When I was doing some research about designing my fuel system, I noticed some companies recommend running them that way. The bypass is used to regulate the fuel pressure on the feed side. It was contrary to what I had always seen and assumed, but I understood the concept. I suppose it might depend on the regulator design and how they recommend doing it. Just my observation while reading...

Edit to add that, I don't think it would be possible to run the regulator after the carbs without a bypass style regulator.

[Falcon67]

For a return system, you MUST use a return style regulator.  The standard Holley thing is for dead head use only.  Plenty of studied have identified dead head style regulation as "sketchy" since the very nature of the regulator switching more/less/more/less surges fuel at the carbs and can add to fuel foaming in the bowls.  For a normal street type car, yea - esoteric type issues.

With a return system, the regulator sits after the fuel log or carb feed(s) and returns unused fuel to the tank.  Line pressure at the carb is set by the amount of return fuel.  With my AFT 250, the line up is a -8AN but the return is -10AN to allow for regulation of that volume of fuel.  In theory, the carb(s) have access to the full volume capacity of the pump, so if pressure reading are dropping it means that the carb(s) and the engine demand are starting to outrun the pump and you need a bigger pump.  I run all the hot rods/race cars with a return system.

[Drew Pojedinec]

Really nice system to purge vapor pressure above. If I had that problem, it is definitely a path I would take.

And Rory’s remark about “should I be seeing an issue after 30 years?”
Serious question I would ask is “Do you honestly think the parts made now, and the parts made 30+ years ago are the same quality?”
I hate to suggest any part that worked for me even five years ago. The cheapening of high quality products is a plaque on our industry.
When I found the electric pump I used worked very well, I bought several of them for just that reason.

[cjshaker]

And Rory’s remark about “should I be seeing an issue after 30 years?”
Serious question I would ask is “Do you honestly think the parts made now, and the parts made 30+ years ago are the same quality?”
I hate to suggest any part that worked for me even five years ago. The cheapening of high quality products is a plaque on our industry.
When I found the electric pump I used worked very well, I bought several of them for just that reason.

Very true statement!! And I'll do the same thing. If I find something that works really well, I'll usually buy a spare right away, because I know they won't be available in probably a years time, or the quality will go down after the next company buy-out    You can apply that to just about every company out there.