Lower numbers are better. Think of P.W.R. as you are next to one of these cars on a track's long straight. The P.W.R. generally will tell you who will win at high speed. Think of T.W.R. as you are next to one of these cars from the green light at the track. The T.W.R. generally will tell you who will win at hard acceleration. Looking at the two numbers will give you an idea how a car will accelerate and maintain speed.