15" vs. 17"

[Bobcat]

tirod ... interesting that you said what you did about the 17" wheels . I also track my ERA and was looking at going to the 17" wheels . Spent some time with a friend of mine who was a team manager Roush/IMSA and other teams and then talked at length with a race tire engineer from Hoosier.... who spends a lot of time at the track working with race teams . Long story short , they both talked me out of going to the 17" tire/wheel combo . Hoosier saw no advantage . His comment was that if the OD of the 15" combo was 26.5" and the same for the 17" combo , for the same tire size , the footprint was no bigger . It would also change my effective spring rates ( higher ) because the shorter sidewalls were stiffer .
So far , I`m spending my time and money on better brakes/pads ( I know a brake man with Roush ) , shocks and springs ( Hyper coil ) , suspension settings ..... and track time .
I think where some people feel that the 17" combo is faster/better is because they were able to go to a slightly bigger tire size .... or as you said , better brakes .... or maybe their springs were too soft .
Any way , that`s my story and I`m sticking with it .