Universal Fuel pump for 1973 2.4 liter S twin plug motor

[x98boardwell]

Currently, I am running a Purulator 42S but it is only pushing 1.9 psi... which is way low for my Weber 40's which were completely rebuilt. I am in need of another pump. My motor is an 2.4 liter S motor and twin plugged.

Any place (like Napa, Orielly, etc.) that sells a pump that will give me a legitimate 3.5 psi that I can buy over the weekend and put on? If not, what do I need to purchase?

It is for a 550 Spyder with that motor in it... great car, just trying to dial it in.

Much Thanks!!!

Bryan

Here is a pic.

[303462]

I have this Bosch factory rotary fuel pump off a 71 911T with Zenith carburetors. has the factory bracket. A little quieter than the Facet , and a little more Porsche correct. Came off a running car. $200 if interested. Cool car!

[911pcars]

For a deadend fuel supply system, an Airtex from the LAPS. I don't have a part number, but get the one that outputs 4psi. When installed up front and after a fuel filter or two, it drops to 3.5 psi.


(borrowed photo)

If you have a fuel return line in the Spyder, you can use a higher pressure pump throttled down to 3.5 with a pressure regulator.

Sherwood

[x98boardwell]

Thanks for the help. No sure if I have a fuel return line but I don't think so. There is a few pumps that I found on Autozone's website that are Airtex along with a couple Mr. Gaskets... Here is the info.

1) Airtex E8902, 2.5-4 psi, 25-30 GPH, 5/16 fitting
2) Airtex E8090, 5-9 psi, 30 GPH, 1/4-18 fitting
3) Mr. Gasket 42S, 2-3.5 psi, 42 GPH, .375 fitting
4) Mr. Gasket 12S, 4-7 psi, 35 GPH, .375 fitting

Does anyone know which one of these would work best or if there is another option that may work better?

Lastly, is it bad to run my car at the lower 1.9 PSI...? if so, what is it doing to my motor?

Thanks,
Bryan

[x98boardwell]

I also found these... trying to figure out which ones will work or what may be best option..

5) Bosch - BSH N69405, 3.5-5.5 psi, 23-30 GPH, 3/8 fitting
6) Napa AFP E8363, 2-3.5 psi, 20 GPH, .325 fitting
7) Napa (Airtex) E8128, 4-6 psi, 26 GPH, 1/8 & 3/32 fitting

Update, when I started the car this morning the pressure was just above 2 psi, but barely. Not sure if this is due to chilly morning (50 or so) or the pump is starting to build pressure. I need to get it off jack stands and take it for a spin I guess. I am guessing the fuel pump will be a continued issue and should be replaced... I just don't know what that low pressure is doing to the motor or how the motor would respond differently if pressure was raised.

Thanks,
Bryan

[911pcars]

Before condemning your FP, connect a pressure gauge to the output of the pump and observe the pressure. The lower than spec pressure could be due to a restriction in the fuel line (e.g. kinked line, clogged fuel filter(s), etc.).

Max. 4psi.

Sherwood