Holley fuel pump pressure

[yamahasrx26]

I have a blue holley fuel pump 34R 7446B with a blue regulator part #34R 6657B the regulator was spraying now and then out of the locknut which was tight( think there was a pinhole in the end of the regulator).....the new holley regulator 12-803 to replace it has to be set for correct pressure the range is from 4.5-9psi so my question is

what's the right pressure for a 2.4 bridgeport with carbs (All stock)?

Can I just go by the same # of threads as my old regulator?.....the new one looks to be the same.....If the pressure is not correct it will either flood the carbs or starve it correct?


Thanks guys :thumbsup:

[Eagle One]

5-6 PSI running at idle will supply ample fuel and not push by the needles and seats.

[yamahasrx26]

so if I have 5-6psi at idle I am golden?

[Eagle One]

Well I don't know if you're a Golden but my daughter's married to one.!!! 5-6 psi with a Holley 110 GPH pump (blue pump rated at 110 gallons per hour) will give you more than enough fuel flow for your application. If the pump and regulator are working properly your pressure won't vary over about a quarter of a pound at wide open throttle. If your pressure drops more than that you have either a bad pump or regulator or a restriction in the fuel delivery to the pump. Run nothing smaller than a 5/16 fuel line and be sure you don't run one of those chrome plated see thru glass filters everybody thinks are so wonderful looking. They have a 1/8 inch hole to pump thru internally and will restrict the flow. Run a metal case INLINE filter preferably with a 3/8 in and out on each end. Fram, Wix, AC, NAPA and most everyone make the same filter. I do not recommend the water separator style in a performance application..

[Eagle One]

Use a gauge to set the pressure!!!!!

[930turbo]

Once you get your static pressure set, you can flow test it to ensure you have sufficient volume to support the power your motor can make. I installed a tee near the top carburetor so I could access the delivery at the carbs, past any potential restrictions in the rest of the system. Attach a hose to the tee so you can capture fuel in a container and measure volume vs time. You should have no less than 11% of your rated HP in GPH. I fought a delivery issue for quite a while with jetting that of course never got any better until I discovered insufficient delivery volume. By the way, it was that said fancy glass in-line filter Eagle mentioned that was the problem.