A lot of it is preference. I used to have fuel going into my cab- not smart. Using a fuel pressure isolator is a better method to use the low cost gauges (which is accurate). It’s basically a disk with a bladder inside. It mounts under hood. So fuel goes from a “t” to it. The other side is filled with an oil, like mineral oil (aka baby oil) for instance. Then a 1/8” metal line goes into the cab to mechanical gauge. If it ever leaks it is just a few drops of baby oil. No raging fire concerns. Leroy used to sell them, not sure if he still does.
electric is more expensive but far easier. Electric gauges from the late 70’s and through 80’s had higher failure rate besides being more $$. But now they are reportedly as reliable when you get a quality one.
Fuel Pressure, 0-15 psi
www.jegs.com
Then a few guys I know have been using oil pressure instead and has been working fine for a couple years now.
LED 2-1/16 OIL PRES BLUE
www.jegs.com
The guy that got that one just made a face that covers the words.
There are cheap ones like this, but you need to do homework to not get a piece of junk:
Interchange Part NumberIP-OPM-01, Car Oil Pressure Gauge. 1 x Oil pressure gauge. ColorBlack Face, Blue LED. Color: Black Face, Blue LED. 1 x Sensor.
www.ebay.com
Personally, I want to make my gauges match so I will use a factory hummer oil pressure gauge, open the face and alter “oil” into “fuel”. Then I will get 2 sensors, one tapped at the ip inlet, the other at the filter housing inlet. They will wire through a single pole single throw momentary switch or button, then to the gauge. This will give me non stop reading of the fuel pressure at the ip. Then when I hit the switch/button, i will see the difference in pressure pre and post filter. That will allow me to determine when the fuel filter needs replacement based on being plugged, not just a random mileage. I plan to sell my ffm and get the fass system of lift pump for the oldest dodge cummins with’fass filters for better filtering, and no water bypassing. That pump turned all the way down outputs 4.8 psi, so I can set it tom5 psi for my db2. Later if I put on a built db2 I can turn a screw and bring it up to 28 iirc.
The time on filter change recommended by gm is of course based on conservative plugging of filter that was determined back in 1990. Station conditions change, and obviously the fuel did as well. The other thing I am considering is doing electronic lift pump pressure control like ‘mean green h1’ did. So that would basically be a rheostat dial on dash that turns up and down fuel pressure with a knob.
