32 psi is pushing it with out head studs. Mine used to hit 31-32 before I got it reflashed, now it only does about 28. I'm sure the updated strategy lowers it, I didn't do anything else. At 32 pounds, you are in danger of lifting the heads off the block and pushing a gasket out due to the weak headbolt design.

 

When these engines were built, Navistar used Torque-to-yeild bolts (TTY) instead of studs. Meaning they will stretch after a certain point....head studs like ARP won't. If the engine hyrdolocks (excessive fuel or coolant) or too much boost (above 30psi) there is a good chance it will lift the heads thanks to those TTY bolts. Those that were lucky to have their truck lift the heads while still under warranty usually had studs installed when the repairs were made...they had to pay for the studs separately, but several dealerships would install them while they had the heads off. I wasn't one of those lucky ones...so I'm still running TTY until I get around to that project.

Short burst of 32psi is alright...but if it was doing it allot I'd be concerned. Mine has peaked 31-32 pulling the 5th wheel up a interstate pass....and had I left the cruise to it's on devices. When your building boost like that there's also a good chance your EGT are starting to get high (above 1200F)...again, short burst are okay; long periods are bad. When I'm running light, without one of the trailers I can hit 28-29 (according to the EV2) if I do a wide-open blast down the on ramp...got to exercise those turbo vanes routinely too keep 'em from sticking

 

In my op. if your pushing over 28 psi on stock bolts your asking for trouble. A stock engine shouldn't go over that unless something is wrong.