Ok my gauges are all in but I am confused with my fuel pressure numbers. It is only reading 10 psi. The pressure is rock solid as the needle barely goes down at WOT. I tapped into the fuel line near the VP44 for my connection to the isolator.

Most of the FASS users are seeing 15-17psi. Is it more accurate to use the port that is on the FASS?

 

Forgot to mention that I changed the fuel filter today to see if that would make a difference; it didn't. There are also no vissible leaks at any of the fittings or fuel lines.

 

Who did you get yours from? Mine is tapped in about 12" from the vp-44 and I see 18 at idle and 15 wot. Different venders can set them up for various press. I heard there is a bypass spring you can set to change the pressures. Tim

 

did you plumb the FASS into the stock line at any point?? i.e. lift pump, fuel filter housing...

 

Bought it from Jannety Racing and bypassed everything stock.

 

I believe your press are what Brad at dpp sets them initially. Some vendors turn them up. I will find out tommorrow how to do it if you can wait. 10 psi will not cause any problems but I know you can change it if you want to. Tim

 

hmmm... you should be seeing higher pressure then that.... lately I've been seeing 14.5-15 idle/cruise and 14-14.5 WOT....

I bought my FASS from Western Diesel Performance but I'm fairly certain it was shipped directly from Diesel Performance(Brad's company)

 

I wasn't going to try the built in port on the pump till the weekend.

 

you shouldn't see but a minor difference in your pressures by using the port unless there is some sort of constriction/blockage in your fuel line.

might need to adjust the spring to get higher pressures....

 

I was also wondering if it might be due to too much air in the tube that runs from the isolator to the gauge itself. The instructions said to fill the tube with coolant if the tubing was longer than 6'. It looked like it was less than 6' so I didn't.

 

could be.... you might fill that isolator tubing with a 50/50 mix of water and coolant and see if that changes anything....

 

I will give it a try to see if it changes anything.

 

Hey graphitecumnz, could you go into a little more detail in regards to adjusting the spring? I remember reading that you can cut the spring down, but don't remember if that was to lower the pressure or raise it.

 

Forgot the isolator and plumb it directly to the gauge. To many things to go wrong with an isolator. Cutting the spring lowers the pressure. Stretching the spring raises it.

 

I bought mine through Forest City Diesel and it keeps the 16 psi gauge pegged at all times.