I've read that the Lexus GS400 is capable of attaining 180mph if its speed govenor is disabled. It does have a low drag coefficent and a short frontal area. So do you think this could be true? The car is governed to 150mph and I've had my GS400 to 145mph myself and it was still accelerating strongly......... Also, why is it that the IS300 has the same top speed as the GS300 (143-144mph). The IS is lighter, more aerodynamic, and has a shorter frontal area. Does it have to do with the final drive ratio?