Via the higher than RWD (or FWD) driveline loss. At 25% expected IT gain the car should put down less whp than a RWD car, and make less hp/weight.

So, probably more of a "hp" penalty -- sorry to be confusing on that.

Quote Originally Posted by ed325its View Post
So if there is no adder (to calculate weight) how is there a weight penalty?

Would like to understand as there is a 325xit in my garage that might be an interesting project.