what is the highest pyro temp to run with stock engine to be safe and not hurt anything and whats highest boost to run?

 

cummins will run 1250 on the pyro all day long. ( pre-turbo) mine sees short burts of 1400+ but no more than a couple seconds. and stock turbo, anything above 35 psi is hurtin more than helpin

 

Dont go over 35psi on the stock turbo or you have a chance of over spinning it. Pyro wise, Cummins suggest no more than 1250 for constant temp, you can go higher, for a few secs, but be care full and be warned if too high or to long it WILL melt valves, piston rings, score walls and more. And a pyrometer is highly suggested.