OK fellas, heres the story. I just ordered my FAST XFI for my 95Z. It comes with the Main harness, Ignition adapter harness, Fuel pump/fan harness and Injector harness, ECU and WB O2. FAST says I will no longer need my stock PCM at all. I take out the factory PCM and harness and run there harness'. My question is what controls the guages in the dash (oil pressure, temp, fuel level, RPM, MPH, etc.) stock PCM? Body Control Module? Something else? I've talked to a few people who said they had to maintain there stock PCM to control these things. HVAC and EGR deleted so I dont care about that stuff. Do I need to piggy back the FAST to the stock PCM? Have some sort of adaper harness built? Any help on what I need to will be GREATLY appreciated. Thanks, Rob.

 

On your car, the dash instruments are driven by independent sensors (oil pressure, temperature, etc) except for the speedometer and the tachometer - those are driven by the PCM but I assume the FAST ECU will take care of those for you.

The people who said they needed to retain their PCM probably had an LS1 car - the instruments are driven by the PCM. So, you should be OK.

 

Thankyou very much. I cant wait for everything to get here. I'm hoping my T-trim will be the new limiting factor in making horsepower . Thanks, Rob.

 

You might want to check with these guys http://www.fasttrackperformance.com/

It may be cleaner to keep the stock PCM in and not have to worry about the wire harness, tach, and speedo.