Lower unsprung weight, what is the advantage?

[Racingf1]

Thanks. That's interesting. I've always been keen to lose unsprung weight, and realised I had the perfect opportunity with
My Mini Cooper.
I decided to change from Pirelli RunFlats to continentals on the front so I could dyno test the difference. I weighed the wheels and tyres and the continental premium contact 2 was 3.6kg per wheel lighter.
I did three runs on each for consistency and found that on average the lighter tyres delivered and extra 2hp.
As I was only testing the front then the equivalent could be applied to all four when on the road so a total of 14.4kg reduction in unsprung weight and rotational mass resulted in a total of 4hp increase in performance. Not to mention the far improved handling and comfort too.
Has anyone else done similar tests and found the same?

[GordonGekko]

sminky said:

How come you don't see inboard brakes to save unsprung weight? i.e. discs on the driveshafts before the joints

Car makers using inboard disc brakes include lotus, Jaguar, Bizzarrini, Iso. There are probably others