Thanks Jean...I'll do that.

 

I have never seen 1.4 on MPSC's on a flat turn in about 40 different cars and about10 different tracks. I mostly look at AIM data and only a few Motec systems, but the few Motec's I looked at were consistent with the AIM data. Most of my data is on Porsches. Thus, it is highly likely that your data is wrong. If you don't believe me, ask the professional data anaylysis engineers at Precision Automotive Research (yes they do this for a living) and they have thousands of cars on most of the US tracks.

On my car and most similar cars, I can prove 1.1 is the lat g limit as I can present data including spins, where ... you guessed it, the peak lat g was about 1.1. ;(

 

Colourchange, I waited a bit to reconfirm my initial thoughts. Verified on Motec datalogger on the factory 997 Supercup cars of David Saelens, Bergemeister and Fabrice Walfish...on Michelin slicks, lateral Gs 1.7 is usual, peaks of 2.1 Gs. If Chris is seeing 1.4Gs maxiumum, there is something wrong with his setup, I see that on Hoosier and MPSC on my car as I said earlier, and there is nothing wrong with my equipment (maybe slight bankings but nothing major for sure).

 

Jean: Banking has a large effect. That may be the difference in our data. Supercups will also show some downforce, especially if over 80 mph. 1.7 is really high on a flat turn. How fast? I think df or banking has to be involved here even on a highly prepared car.

 

I have three questions for the experts here.

1. Isn't "banked turns" generate vertical Gs and not lat Gs? On a GPS system would show Lat G but on a in car logger, that shouldn't show up right? Unless the logger is combining the Gs to give total G.

2. I remember reading somewhere that 0.02G is "significant" difference between the cars being tested in the mags. So shouldn't 0.1G be really significant when it's only a tire change?

3. Does the graphs by ColorChange shows that the driver is incredibly inconsistent? Seems on MPSC, the driver is a lot more "jerky" while on PS2 is smoother. A graph like that could demonstrate "hard data" to compare tires?

I have both PS2 and PSC, and I could attest that PSC is much more responsive and grippier.