Blog on Cayman S vs. GT3

[FTS]

As I am looking at data, few interesting points about the cars and my driving emerge, so I thought I'll create a post about it to document over time.

Context:

• 2006 Cayman S, stock with Sport Chrono and PASM, new R888 tires, PFC front rotors and Hawk HT-10 pads, weight w/half tank: 3056 lbs.
• 2010 GT3, stock with Sport Chrono and new R888 tires, stock rotors, RS-19 pads, weight w/half tank: 3195 lbs (+139 lbs).
• The CS data is from Zone 2 VIR event in March 2010, ambient temps ~40F
• The GT3 data is from Zone 2 VIR event in March 2011, ambient temps ~40F
• Same driver, but with the GT3 I have ~10-12 more track days.

First, here are how the GPS track map is, and how I configured my sectors on it:

Next is each car's sector split timing, and min/max values per sector:

And here are G-G plots for each car's fastest laps:

To be continued...

[FTS]

[Gator Bite]

Fatih,

You are such a geek... I love it (and hope to be an equal geek someday).

[FTS]

Yeah, I know. As I mentioned in another thread, I have to force myself to learn, this is the only way for me. Wait till you see my GT3 vs GT3 analysis, that one is absolutely nit picking

[TRAKCAR]

Cool. Now get a coach and do the before and after in GT3!

[bman]

Or let me drive it for comparison

[TRAKCAR]

Or let me drive it for comparison

[FTS]

^ what he said LOL.

Actually it is not a bad idea Brian. And we can also hook up my logger to your car and collect data for comparison.

By the way, I got a coach Ain't telling more

[FTS]

It is interesting that one magazine went to the extent to make some hard measurements on vehicle configurations and associated performance that actually validates our "feel."

Car and Driver has a test of Cayman R vs. 997.2 GT3 in their July issue. The results should not be surprising, but they got some data that is quite relevant. The most important numbers to me are the ones that no one goes out to measure, compare or publish, it is refreshing to see this mag went to that extent; they employed Cayman Dynamics, a company that specializes in vehicle dynamics with multi-million dollar equipment and engineering talent.

So, the GT3 CG height is 17.4" vs. 18" for Cayman R. The exact location of CG is not revealed though, and also keep in mind that the Cayman R sits 10 mm (0.4") lower that even Cayman S w/PASM.

GT3 Polar Moment of Inertia is 1184 ft-lb-sec(2) vs. Cayman R's 1515.

The Static Weight Distribution, GT3: 39(f)/61(r) vs. Cayman R: 45(f)/55(r)

Dynamic Weight Distribution, under acceleration, GT3: 26(f)/74(r), CR: 33(f)/67(r)

Dynamic Weight Distribution, under braking, GT3: 58(f)/42(r), CR: 64(f)/36(r).

Forget all other test and numbers, these are enough to explain what we "feel" that the 911, particularly the GT3, is truly the better platform, long live rear-engine config