With a few more tweaks and test sessions, Project Cayman X51 may have won this shootout. Its power, brakes, and handling were up there with the modified 997 S. More experimentation with alignment and tire pressures would have likely further improved this freshly completed project. But you can't win them all. The Cayman was the favorite for speed and driving excitement, providing the driver with a thrilling racecar-like experience. It was interesting to note that the unique handling nuances of the equally powered Cayman X51 and 997 S didn't signal a clear winner. The Cayman's 46:54 front/rear weight bias seemed more stable corner entry to apex, while the 997's 39:61 weight bias was better apex to corner exit. Slow in, fast out has always been the racer's maxim. It seems Porsche has known this all along.
The Verdict
The 997 S reigns supreme. Our test car's bolt-on power mods equaled those of our custom Cayman X51. Chassis additions included only anti-roll bars and lightweight wheels, while a more aggressive track-biased alignment would further improve our winner's handling. It is hard to beat a 911 at the track when it's driven well. Why is it so good? I believe the tail-heavy 911 gains its advantage in being able to get the power down on corner exit. Improved grip is achieved by the combination of additional rear weight, rear-wheel drive, and useful rearward weight transfer. Our test subject 997 S also had a larger rear contact patch with its chubby 305-width tires.
Project Z4M represented itself surprisingly well here, while Project Cayman X51 proved to be an extremely exciting, albeit expensive, track-day warrior. The 911, however, remains the legend, and the benchmark to beat. I have a funny feeling that my next project car will begin on a 911 platform.
The legend-Porsche Carrera 997 S
The 997.1 S is truly a brilliant car, this example coming from the factory ready to go with the cockpit adjustable PASM suspension and carbon ceramic brakes. The vehicle's owner completed some research on his own and put together a very sporting package to bring the car up to his desired performance specifications. GT3s are scarce in his neck of the woods; this is the next best thing.
2008 Porsche 911 Carrera S
Layout
Rear engine, rear drive
Weight Bias: 69:61
Curb Weight: 3,250 lb
Options
PCCB Brakes, full leather interior, sport seats, carbon trim
Engine
3.8-liter flat six; stock power 355 hp
Engine Mods
AWE headers, metallic cats and mufflers, EVO intake with K&N cone filter, GIAC software
Peak Power
395 hp (est.)
Driveline
Six-speed manual
Suspension
H&R sway bars
Brakes
OEM PCCB assemblies
Wheels
Champion Motorsport, 9x18, 11x18 (f/r)
Tires
Michelin Pilot Sport Cup R-compound, 235/35, 305/30 (f/r)
Exterior
N/A
Interior
CG-lock
Final Costs
$80,000 + $10,000 (mods) = $90,000
| TABLE 1: THE BLOKE’S HARD DATA |
| Car | Lap Time | Average Speed | Peak Speed | Max g-Force | Max g-Force | Max g-Force | Time on Brakes |
| | (sec.) | (mph) | (mph) | Acceleration | Lateral* | Braking | (sec.) |
| Z4M | 92.15 | 75.40 | 126.1 | 0.48 | 1.28 | 1.05 | 16.85 |
| X51 | 91.25 | 76.15 | 134.1 | 0.50 | 1.32 | 1.09 | 15.35 |
| 997 S | 90.45 | 76.89 | 133.9 | 0.54 | 1.36 | 1.16 | 14.90 |
| *relative measurement, lateral force reading about 20% high. |