What kind of temperature readings are you getting? Where are you measuring?
At some distant, not too relevant point of reference, I have measured my 2.7 (fully warmed up), pre-'74 heat exchangers with a surface temperature of almost 400ºF (measured at the collector junction).
The EGT is a function of the air/fuel mixture and, in your case, boost pressure.
I would be more interested in the EGT's during cruise and especially WOT. For that you need a proper EGT gauge and sensors, preferably 1 in each exhaust runner to reveal what's really going on (a malfunctioning injector is not good to have under boost). I believe in the neighborhood of around 1300-1400ºF for turbo engines is the norm. However, can't speak accurately for real-world 930s, even less so if boost pressure is higher than stock.
Sherwood Lee
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