[buster]

I installed a Holley fuel pressure gauge on my Holley fuel line and the needle bounces constantly but consistantly. The only time it is steady is at hi RPM's. Is this right?

Also, what should the fuel pressure reading be at idle and at hi RPM? I have a 350 with a stock fuel pump.

[toobroketoretire]

Originally Posted by buster

I installed a Holley fuel pressure gauge on my Holley fuel line and the needle bounces constantly but consistantly. The only time it is steady is at hi RPM's. Is this right?

Also, what should the fuel pressure reading be at idle and at hi RPM? I have a 350 with a stock fuel pump.

Yeah, the bounce is normal for any pump running that slow. Only an oil dampened gauge will stop the bounce but they're expensive. And the pressure should remain at about 5 psi during all operating conditions. But to truly know what your pressure is under a full load you'll have to run a hose into the cabin like I recently had to do.

[fishslayer143@yahoo.com]

it bounces with the pulses of a mechanical pump..5-6 psi at idle

[buster]

Originally Posted by fishslayer143@yahoo.com

it bounces with the pulses of a mechanical pump..5-6 psi at idle

Thanks, thats what I get at idle.

Originally Posted by toobroketoretire

Yeah, the bounce is normal for any pump running that slow. Only an oil dampened gauge will stop the bounce but they're expensive. And the pressure should remain at about 5 psi during all operating conditions. But to truly know what your pressure is under a full load you'll have to run a hose into the cabin like I recently had to do.

Understood. BTW, I get 8 lbs while holding at 3k RPM.

[toobroketoretire]

Originally Posted by buster

Thanks, thats what I get at idle.



Understood. BTW, I get 8 lbs while holding at 3k RPM.

You need a pressure regulator to reduce it down to 5-6 pounds. Holley's specs call for between 5 and 7 psi so 6 psi is a happy medium.

[buster]

Originally Posted by toobroketoretire

You need a pressure regulator to reduce it down to 5-6 pounds. Holley's specs call for between 5 and 7 psi so 6 psi is a happy medium.

K, thx. I will look into getting one. Maybe this is why I experienced a couple of stall-outs?

[toobroketoretire]

Originally Posted by buster

K, thx. I will look into getting one. Maybe this is why I experienced a couple of stall-outs?

It's possible your gauge is wrong so if you happen to have another gauge try that and see how they compare. If your carb flooded it would cause a stall at idle for sure but not necessarily at highway speeds.

[fishslayer143@yahoo.com]

Originally Posted by buster

K, thx. I will look into getting one. Maybe this is why I experienced a couple of stall-outs?

8psi will overpower the floats and cause flooding when you let off throttle .. get a regulator and set between 5-6 psi

[buster]

Originally Posted by fishslayer143@yahoo.com

8psi will overpower the floats and cause flooding when you let off throttle .. get a regulator and set between 5-6 psi

So 5.5 lbs. Max would be good for all RPM's? BTW, would this make the gauge read steady or would the gauge still be affected by the pulses of the pump?

[fishslayer143@yahoo.com]

my gauge is on the regulator itself and still bounces slightly.. I too had 8psi at 3000 rpm from my Holley mech pump.., when I hit WOT, and then let off, it would flood .. regulator prevents that...I set mine at 5.5 psi, and that feeds my stroker just fine