Help on where to hook a fuel pressure gauge Big Cam with a PT pump

This one.

 

Sorry. I answered your second question first.
Yes to the diasy chain for the stc.

 

If it doesn’t smoke at idle or much when cold the stc should be working pretty good. Also they have been known to blacken and dilute the oil a little more when turned up than fixed time because the fuel pressure well get fuel past the the stc solenoid and mix with the oil.

 

You have three steel lines coming straight up from that pump. The one in the center is for the air fuel control. Disconnect it from the after cooler at the other end and pressure test the diaphram in the pump. I use a homemade hose connected to a radiator pressure tester. Then pump it up to twenty PSI. It should hold pressure. Probably need to replace the rubber seal it the bottom if you have disturbed it.
Make sure the fuel pump throttle lever breaks over pedal down.

 

Are you talking about this line? It should go to the other port on the top of the pressure head right above were you need to install the gauge.

 

Do what @BoxCarKidd says. 90-95% of the time if everything else is healthy and power goes down that afc diaphragm is the culprit. The new ulsd fuels eat them up. Cheap and easy to fix.

 

Its part of the stc. It will not run good without it. You are gonna have to tee it.

 

This is how I did two of mine. I have fuel pressure gauges in the dashs of all my trucks.