Rotating Mass
Thread Starter
Burning Brakes
Joined: Nov 2002
Posts: 1,164
Likes: 184
From: Ohio
Rotating Mass
Lately I have been seeing a lot of coments about heavy wheels and HP loss per extra pound of rotating mass. Can someone calculate how much HP is lost by going to a taller tire...say an 18 and 19" combination? I know proportionatly they are the same but I know there is a loss just like there is a gain going to a shorter tire 
Thanks,
The big dog
Thanks,
The big dog
Pro
Joined: Jan 2000
Posts: 741
Likes: 47
From: Indianapolis IN
It seems that you are talking about two different concepts.
Heavier wheels/tires will cost you horsepower and handling. The amount of horsepower lost or gained due to the rotating mass will vary with the weight distribution of the particular wheel/tire combination.
A tire with a larger outside diameter on your drive wheels will make your axle ratio seem numerically lower. A tire with a smaller outside diameter on your drive wheels will make your axle ratio seem numerically higher.
Which concept are you wondering about?
Heavier wheels/tires will cost you horsepower and handling. The amount of horsepower lost or gained due to the rotating mass will vary with the weight distribution of the particular wheel/tire combination.
A tire with a larger outside diameter on your drive wheels will make your axle ratio seem numerically lower. A tire with a smaller outside diameter on your drive wheels will make your axle ratio seem numerically higher.
Which concept are you wondering about?
