A guy brought me a 72 Blazer he did a engine swap in... 2005 6.0ltr LQ4 using a Bosch 044 300LPH Inline Fuel Pump. Rated for 400-500HP... He's using -6 An fittings with 3/8" Stainless Steel Braided hose. He's also using the Corvette fuel filter Regulator but there is only 45lbs of pressure, I checked for kinks(none) and also there is 13.8 volts at the fuel pump....The filter/regulator is about 2 weeks old sooo I'm stumped! Any ideas???

TIA

 

What is the PSI supposed to be? Also the pressure may lower due to distance from the regulator when the vehicle is running. If the vehicle isn't running, is the pressure still 45PSI? Where are you measuring the pressure at?

 

I'm running the vette fuel filter/reg with an Walbro 255 in tank fuel pump and my pressure is 65psi. I believe you need at least 60psi to run the 6.0,Mike

 

Your supposed to have 58 psi with that reg. Thats what idle PSI should be for the 6.0.

I had trouble with the vette reg. i had, i was seeing 70 psi, too high.

I reccomend ditching it and getting an adjustable setup.

I also have a walbro 255 in tank pump.

 

Yeah, it's supposed to be 58-60 psi... The pump was installed pretty far away from the fuel tank(about 48") and filter/regulator was installed another 36" further still... After key on, ignition off, pressure goes up to 45psi but in less than 3 seconds pressure drops to 0psi...Bad filter/regulator/
Engine running pressure holds at 45psi

I did notice that when key is initially turned on, fuel pressure tester will shoot up to 62psi for a split second & then drops to 45 psi and holds steady...

 

If it isn't running, the fuel pump only runs for about 3 sec unless you jump the wire to keep it running.

 

Ordered new filter (no-one in town has it in stock) and we'll see what happens...