Anybody else seen any similar problems?

I've got Isspro Fuel, Boost, and Pyro. I just got a Edge Juice/Attitude. The Isspro Fuel pressure is installed POST-filter (13.5 psi) and the Attitude reads PRE-filter (25 psi). The isspro is plumbed with fuel right into the cab, no isolator and is a mechanical gage. I have not changed my filter in quite a while or done any other experimenting like swapping them around. Just curious about any thoughts, not too concerned.

Second problem is the Pyro. The Isspro consistenly reads 75* to 100* higher than the Attitude. I have them both wired in parallel to the same probe in the manifold. It doesnt' matter if i'm at idle or 1200*, there is always that 100* difference. I"m just wondering which is right. I always have thought the Isspro read high just from riding in other people's trucks, but dont' know. Any Thoughts on which is right??

As for the Booost pressure, it is within about 1 psi all the time on both.

 

Where does the pyro for the isspro sit when the truck is shut off, or is it an electrical unit?

As for the fuel pressure differences I'm guessing that's normal. Pressure is a measure of restriction and there is obviously more of a restriction before filter rather than after. It might be a good time to swap your fuel filter out and see what happens to the pressure. At the very least the attitude might turn into a great way to monitor fuel filter life?