JP66

Hi Matt or Peter,

So enjoying a nerdy morning of reading data from yesterday's practice at LRP. In the graph below I was comparing my best lap in my Cayman R which had Yoko ADVANS on the car versus Simon's best lap yesterday in my F car (2004 Boxster S) with Hoosier R7s on.

Question: Shouldn't the maximum lateral G force be significantly higher for the Hoosier? Are there differences in the suspension of the two cars that would allow the Cayman to corner equally well with a lesser tire?

Thanks as always!

Joe

ProCoach

Lat G gains for a specific tire only happen when the driver exploits those opportunities...

JP66

So that begs the question does someone have data showing a Hoosier R7 reaching noticeably higher than 1.3g in level turn

ProCoach

Depends on the car, but I would think that's a pretty good number.

Your peak in the graph is under massive compression in the Uphill, so that's not a good comparison. Neither is the Left Hander or the right onto No Name, due to the camber gain. West Bend is the best measure at LRP for a "flat turn."

JP66

I knew geometry would influence the number hence my mentioning "flat turn" but I am disappointed to learn that 1.3g is all you can expect since that is the same number for the Yoko. I really expected a Hoosier to represent a step up to say 1.5 or even 2.0.

So when I see 2.0 on the g meters in Cup Car videos, that represents a much different class of tire?

Bill Lehman

Here's a screen shot of a lap at Summit Point. I'm thinking that the high G corners are pretty flat. R7s on a stock GT4 with track alignment. Pros, I know the G-Sum shows room for improvement.