Even with a new pyro probe, it might be worth it to check the temp independently of the digital read-out. 2600 is what those engines run at high idle. High idle rpm is independent of ultimate horsepower. Several things work together to determine exhaust temperature: engine condition, load, timing, fuel delivery, ambient temperature. injector status, turbocharger, valve timing/cam condition, cooling system. Let's be ready to look at the whole system.

That engine will smoke a little under load, but not much.  1150 on the pyro isn't too high.