Yeah, a race engine on something like T6 or better could run at 0.90 (13.2) and gain 10% better fuel consumption whilst only losing around 5% horsepower as long as the thermal management was setup correctly.

All the stratagies are in place to control thermals on proper management, even Audi S series have it as std nowadays, K Type thermocouples with fuel/spark/boost trim control to manage temps.