Fuel Pump, Supply, Return, Damper Options

[turnaround89]

I just put my fuel pump back in and had some questions about the S R and D on it. I understand that the S, is the line from the tank. the R is return from the carbs, and the D is Damper, however, is the D the line that fuel runs through to the carbs? Its the only remaining option i have for lines, just wanted to make sure?

[type47]

Careful. It sounds like you are using a D-jet fuel pump with carbs. D (and L-) -jet pumps should be too much pressure (about 30 psi) for carbs unless you have some sort of pressure reducer. I think carbs use fuel pumps that produce pressure in the 5 psi range.

"D" stands for druck which is German for pressure so thats the pressure port.

[johnnie5]

You need a different fuel pump for carbs, look here...

http://www.cbperformance.com/catalog.asp?ProductID=577

[Cap'n Krusty]

Unless you're speaking of a 70-71 911 T pump, the pump you have CANNOT SAFELY BE USED WITH CARBS. Even regulated down from over 40 PSI to 3, it's just not safe. Get a nice rotary pump made for carbs, one that you don't have to use any regulator. Yes, S is "suction", from the tank, R is "return, teeing in with the return line from the fuel pressure regulator and on to the tank, and D is "druck", or "pressure" in German. If someone tells you it's OK to use the stock D-jet FI pump with carbs, they're fulla crap. But then, what do they care, it's not THEIR car that burns to the ground .................. The Cap'n

[turnaround89]

Which one from CB, there is a 3.5 and 5.5lb pump?

[effutuo101]

Here is a link for the products I am useing.
Fuel pump. 2-15psi, a spring to adjust from 15-70psi
a regulator to manage my flow with a return line to the tank to keep the gas at the regulator as cold as possible. I am waiting on my carbs to get back on so I can dial in the system.
Phoenix red will be running the same regulator and return system.
With the pressure gague right on the regulator, you can dial this in for your carbs.

http://www.aeromotiveinc.com/products.php

p/n 13301 for the bypass regulator

[SirAndy]

Which one from CB, there is a 3.5 and 5.5lb pump?

http://www.cbperformance.com/catalog.asp?ProductID=577


3193 Rotary Fuel Pump - 3 1/2" lbs. - 12 volts

(IMG:style_emoticons/default/bye1.gif) Andy

[turnaround89]

Ordered up the new pump (IMG:style_emoticons/default/piratenanner.gif) . Now here comes another question. Both plastic fuel lines that go into the engine compartment, will i need both of those anymore? I will have one line that goes into the pump from the tank and then one line from the pump into the engine compartment that splits into two lines for each carb, right?

Thanks Everyone. (IMG:style_emoticons/default/biggrin.gif)

[SLITS]

You could plug off the return line

or

You could get a fuel pressure regulator that incorporates a return to the tank. This way you would have fresh cool fuel to feed the carbs.

Since you bought the pump ... the #1 option is the best ... plug the return line.

[aircraftdesign]

You could plug off the return line

or

You could get a fuel pressure regulator that incorporates a return to the tank. This way you would have fresh cool fuel to feed the carbs.

Since you bought the pump ... the #1 option is the best ... plug the return line.

If one were to use the existing FI pump and use a bypass regulator to reduce the pressure from the FI range down to the proper carb range you potentially could plumb the return back through the tunnel and into the other nipple at the bottom of the tank. This would not be a practical solution during any condition other than when you have a nearly empty tank as the static pressure of a full tank would work against the return flow.

The best solution if you retained the FI pump would require a new return inlet at the top of the tank - probably much easier to get a different electric fuel pump correctly rated for carb pressure and eliminate all the rework and safely operate the vehicle

[r_towle]

When I replaced one of these I looked up the specs.
Its rated at 65 PSI..way to much for carbs.
There are no safe regulators to manage that pump down to 3 psi

Rich

[turnaround89]

thanks everybody. maybe my car will driving next week, little spring break action!!! (IMG:style_emoticons/default/driving.gif)

[aircraftdesign]

thanks everybody. maybe my car will driving next week, little spring break action!!! (IMG:style_emoticons/default/driving.gif)

Not that your goin that way but Aeromotive makes a bypass regulator that handles pretty much any pump out there-

A2000 Bypass Regulator, P/N 13202

Dynamic flow and rock steady pressure make this regulator perfect for naturally aspirated or carbureted blow-through applications. The A2000 Bypass Regulator provides unmatched boost reference and high flow capacity. Compatible with any high volume electric or mechanical fuel pump.