The Panoz gets more power because it weighs more, understeers badly, and eats tires. It has a huge advantage over the competition at La Sarthe, but if we were at, say, Grand Valley, it would be quite a bit slower than cars like the McLaren or the CLK-GTR.
Your lap was very nicely driven, although your smooth driving style would probably be better served in GT5 than in the arcade-leaning GT4.