Three-spoke steering wheel, red taillights, bi-xenon headlights, Sport Chrono package, self-dimming mirrors

Transplanted 3.8-liter X51 flat six; stock power 381 hp

Engine Mods
Custom headers and cats, Supersprint cat-back exhaust with Power Loop mufflers, custom intake with K&N cone filter, custom REVO software

Peak Power
400 hp (est.)

Six-speed manual, B&M short shift kit, HP Sachs clutch

KW Suspensions V3 coilovers, camber plates, Tarrett Engineering anti-roll bars, links, tie rods, rear toe control arms

OEM assemblies with Goodrich stainless lines

Forgeline ZX3-R, 9x18, 10x18 (f/r)

Nitto NT01 R-compound, 245/40, 275/35 (f/r)

TechArt front spoiler, SpeedArt rear spoiler

996 Euro GT3 Seats, Scroth six-point harness, Cantrell Motorsport full roll bar

Final Costs
$65,000 + $40,000 (mods)= $105,000

Hard Numbers and Impressions
After The Bloke finished with each car, I took each out for back-to-back track sessions as well. I was then able to go through Traqmate GPS data and discuss vehicle performance with him. Table 1 summarizes the results of his hot lap sessions.

Each car had particular performance idiosyncrasies which we'll look at below, but let's cut to the chase. According to Table 1, the 997 S was the clear winner in this real-world numbers contest. It won all categories except Peak Speed. We'll start the analysis by seeing what The Bloke had to say:

"Driving three vehicles in anger, back to back to back, is a great experience. It really highlights how similar, and different, three cars can be. Once at speed, and one starts to push each car toward their limits, some clear differences appear. There becomes a gap in the ease-of-use factor. However, this did not diminish any of the fun factor.

"The Z4 M Coupe is a much more involved drive, needing full concentration at all times when driven at the limit; it is always very rewarding when you get it right.

"My overall impressions of the Cayman were very favorable; the car felt light, well damped, and most of all, very fast. After the session I felt that it was easily the fastest car of the three. However, the GPS telemetry told a different story.

"Overall, the 997 S was the easiest car to drive fast. It remained balanced, with very minor corrections needed to keep the car on line. At no time did the feeling of an infamous rear engine vehicle come to mind."

The numbers tell us that both Project Z4M and Project Cayman X51 were fairly defeated in our controlled performance test. But let me point out that each of these cars have come a long way up the performance ladder to compete at this level. Also note that our "OEM Plus" 997.1 S winner tested well above a stock 997.1 S in all-around performance. And when you closely review the numbers for all three, the results are actually incredibly close.

I agree with The Bloke's assessment of Project Z4 M as an involved and satisfying drive-hell, it's my car. The reason for this is the rawness of the chassis feedback through the steering wheel and the seat of the pants. The mildly modified S54 inline six further adds to the driving excitement with improved low-end torque and high-end power, as well as its nasty metallic soundtrack and 8000-rpm rev limit. A major pitfall, however, was its uncertain brake pedal feel, which varied slightly with rpm and reduced driver confidence at the limit. This is by no means an issue with the Brembo brake upgrade; rather, it is the inherent Dynamic Brake Control safety system that includes brake stand-by, brake drying, brake fade compensation, and hill-hold. This factory system does not hold up well when driving at ten-tenths when combined with the Brembos. Interestingly, it behaves normally when driving at nine-tenths or below, and can be overcome with more experience at the limit (i.e., you get used to it).

By Doug Neilson
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