try as i might i can't figure this one out. thinking of replacing a 3.64 with a 3.91(lsd i found in a junk yard). everything i read hear says that the 3.91 will give me faster take offs but lower top end speed. this doesn't make sense to me. if the driveshaft turns once and the wheels turn 3.91 times that should give me more top end speed than if the wheels turn only 3.64 times for every turn of the drive shaft. what am i missing here? thanks for any answers.