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Recommended fuel pressure

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Hi guys - my Bugeye has an electronic fuel pump located in the engine compartment and it was flooding the carbs before stored her.

I bought a fuel regulator but am not sure what pressure I should restrict fuel flow to. What would you guys recommend?

Thanks!
 
set it at 3, that's gonna be about right for most carbs. which carbs do you have? that's important to specify. if your carbs are flooding the problem might be in your carbs, not the pump.

buying a pump that pumps the right pressure would be the best method, although not foolproof. i'm on my 2nd carter 4070 in a year as the first started pumping at a really high pressure somehow.
 
Yes, 3 lbs works fine.

I have my race car set at 3 lbs.
 
hopefully your regulator isn't one of the fancy round chrome ones as sold by the usual suspects. they're worthless. If you need one, get a GOOD one.
 
Pythias said:
hopefully your regulator isn't one of the fancy round chrome ones as sold by the usual suspects. they're worthless. If you need one, get a GOOD one.
Click to expand...

Uh oh... It is, I wasn't aware there are issues with them. Worth trying with a 3 PSI setting?
 
Yes, the chrome circular regulators do not, for the most part, enjoy a very good reputation. I had one of these regulators and found it to be less than reliable in its metering of the fuel so I opted for a Holley 12-804 regulator (1 - 4 PSI).

Fuel Pressure Regulator and Gauge

Mike
 
Yep, I run a Holley as well. Nearly identical to yours, Mio. The nice thing is that in the event of a fuel pump failure, ANY fuel pump can be installed, depending upon what's on the shelf in any town at any auto parts house. Important consideration for those of us driving longer distances.
 
Much easier to use the correct low pressure pump.
 
Or or or, Moss for a proper pump.
 
Fair point Jack, but I think Bill L. makes an interesting point. I do some touring in the cars and being able to coast into a local parts store and then power away is a nice plus...
 
I can't remember where I found the best price. I did a Froogle search for the above mentioned Holley regulator. I added the gauge later, as they come set at the factory at about 2.5 lbs. ..

Jack makes a good point as well. If you use the correct SU pump, you don't need a regulator. At that point, cost and convenience become issues, as well as ones desire for originality.
 
I installed a Facet pump. It put out 3.5 PSI blocked off, which was exactly the same as the mechanical pump. Eventually, though, I had problems with it forcing fuel past the float valves, so I added the Holley regulator and lowered it to 2-2.5 PSI. The Holley regulator is a nice unit--I'm amazed that it regulates well with only 1 psi of pressure drop. Seems to stay in adjustment well, too.

I do think the arguments in favor of a generic pump, with a regulator, make a lot of sense.
 
Sarastro said:
I installed a Facet pump. It put out 3.5 PSI blocked off, which was exactly the same as the mechanical pump. Eventually, though, I had problems with it forcing fuel past the float valves, so I added the Holley regulator and lowered it to 2-2.5 PSI. The Holley regulator is a nice unit--I'm amazed that it regulates well with only 1 psi of pressure drop. Seems to stay in adjustment well, too.

I do think the arguments in favor of a generic pump, with a regulator, make a lot of sense.
Click to expand...

I'd like to chime in on this thread rather than start a new one... Are you using a Weber carb? How can you tell what your electric fuel pump output should be? Right now, I'm getting <1.5 Quarts/minute. How do you measure this and how can you tell if the pump is or is not putting out? I'm at a lack for any tricky instruments to measure the PSI. I'm still struggling with getting this car to run. HELP!
 
You can get a gauge for measuring the pressure for a few bucks from any auto parts store (or Harbor Freight), and sometimes they are set up to measure vacuum as well. Very useful thing to have.

I'm using plain ol' H1 carbs, but I'd expect the same thing to be true of Webers. You just need enough flow to keep the float bowl full, and enough pressure to move the fuel through the lines and get it up to the carbs, which isn't much. I wrote up an article for the Wiki, under "General Technical Articles" on installing a fuel pump. It might be a little too much information, but it's there in any case.

By the way, a quart per minute is plenty of flow for these cars. Think of it this way--that's 15 gallons per hour. If you get 30 MPG, that'll support a constant speed of 450 MPH. I know, that's not enough for some of you, but for me it'll do.
 
Sarastro said:
By the way, a quart per minute is plenty of flow for these cars. Think of it this way--that's 15 gallons per hour. If you get 30 MPG, that'll support a constant speed of 450 MPH. I know, that's not enough for some of you, but for me it'll do.
Click to expand...

Funny, I'm just trying to get it out of the garage! I'll be happy if I can go 25MPH.
:cryin:
 
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