Thanks, love the black when its clean (as I am sure you are familar).
Boost is around 50 psi. I have the blow-off valves set at 60 psi, but I am not able to reach that high. My guess is the 4500 ft altitude. Anyway, at lower boost levels, 30-40 psi, EGT's can reach as high as 1300 degrees (either on a dyno or pulling a 9,000 lb trailer), but as the boost rises up toward 50 psi, the EGT's drop to around 1150-1200 degrees.
Interestingly, I was hauling a Bobcat skidsteer back from Idaho last weekend, and cruising at 85 mph, the EGT's were around 800. Only under hard acceleration, or climbing a grade did the EGT's rise to the 1150-1200 level.
Peter