Which type of pressure gauge do I need on my 05? I see they make a pressure gauge that reads from 0 -30 PSI which I'm guessing monitors the pump pressure and then they make a rail pressure gauge that reads rail pressure. Which one of these two would be the best to monitor? And where do you install the gauge for the pressure reading?

 

I would do a Rail Pressure Gauge.

Isspro EV2

 

Do the rail pressure guage and put the 0-30 guage inline before the CP3. Don't run more than 15psi for daily driving any more is bad for the CP3. Then those bases are covered!