You can either cook it at your regular temp, and knock about 15 minutes per pound off the cooking time, or lower the heat and cook it the same time.
I just tried an experiment with a roast chicken using my convection for the first time; cooked at regular temp for about 45 minutes, and the bird was beautiful, lots of brown, crispy skin and oh, so moist and tender.
Wow - a 7 1/2 pound turkey - would that be a turkette?