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View Full Version : Fuel pump questions for weber set-ups...


sen2two
09-04-2010, 04:28 PM
I have 3 weber set-ups right now.

45 sidedraft
48 sidedraft
51 IDA (yes, the real deal Racing Beat 51 IDA :001_005: )

What type of fuel pressure will each be looking for? What size fuel pump? I have used the blue Holley fuel pump before, but i think it was to much pressure?

51 IDA will be on a full PP 13b. The other two will be on moderate to stock motors. Nothing wild for those.

Any tips would be great. Thanks.

730RWHP12A
09-04-2010, 06:00 PM
3.5 psi is recommended for weber carbs mallory, carter or holley will work fine when ran with a fuel pressure regulator set at 3.5 psi..
however depending on the needle valve in the 51 ida we ran ours up to 6 psi with a internally regulated Mallory 140 fuel pump. we had issues with fuel starvation with other pumps on the p-port....

sen2two
09-04-2010, 09:04 PM
So this one carter pump should be suitable to run all three pumps just fine then. Reason being, I plan on running my basically stock motor at first with my 45 webers because its ready to go. Then later dropping in my 6 port full bridge motor that has the 48's on it. And when i finish my PP motor with the 51's on it, drop that in. I don't want to get a new pump with each motor change.

http://www.jegs.com/i/Carter/180/P4070/10002/-1?parentProductId=748050

730RWHP12A
09-04-2010, 09:12 PM
you will need a better pump for the p-port. the carter will not flow enough volume too keep up with the p-port. if you want to buy one pump then get the mallory 140 and your done.

jtbshaw
09-08-2010, 02:43 PM
Aww snap, I'm glad Robert posted in here about this. I just got my setup fired up on Monday night....TII with tha Shack's 45DCOE blow through. You are suggesting only 3.5lbs Robert? I'm runnning an Aeromotive A1000 pump and regulatin' with a Mallory 4309 FPR. I had it set to 6psi...too much???? The 4309 is a progressive FPR.

Todd B.
(had any of that crazy sauce lately?)

Buggy
09-08-2010, 05:02 PM
I know at anything over 3psi on my 48 IDF i had problems with fuel being pushed past the needle and seat and also external fuel leaks from the carb. Keep the pressure low, but go with a larger needle and seat along with a high flow pump. I'm running a 3mm needle and seat on my halfbridge in my Rx-4.

jtbshaw
09-08-2010, 06:14 PM
That would explain why the car seems to be flooding without ever touching the pedal. I have the pressure set at 6psi. I'll turn it down tonight and see what happens. I still have to dial the timing in as it is a tooth or so off. One thing for sure is that I am not having a lack of fuel.

Thanks for starting this thread Sen2 and thanks for the input fellas.

Buggy
09-08-2010, 08:37 PM
That would explain why the car seems to be flooding without ever touching the pedal. I have the pressure set at 6psi. I'll turn it down tonight and see what happens. I still have to dial the timing in as it is a tooth or so off. One thing for sure is that I am not having a lack of fuel.

Thanks for starting this thread Sen2 and thanks for the input fellas.

You could actually watch the fuel drip from the tubes in the barrels of the carb after the car was shut down. That's how I figured out what was going on.

sen2two
09-09-2010, 09:42 PM
I found a great deal on a basically new Holley Blue fuel pump.

Preset to approximately 14 psi
Flows 70 gph maintaining 9 psi line pressure
Free-flow capacity of 110 gph

If all you need is it to maintain 6psi for a full PP. This should be a nice pump also...