2012 Jeep Grand Cherokee SRT8 vs. 2013 Porsche Cayenne GTS Track Test

The last time we put the Jeep Grand Cherokee SRT8 up against the mighty Porsche Cayenne, it wasn't exactly a fair fight. The Porsche was packing twin turbos on top of its 4.8-liter V8 engine, while the Jeep was forced to get by on its 6.4 liters of displacement alone.

OK, so it's hard to cry any tears for the Jeep, but this time around the Porsche in question has a little less help. Instead of the mighty Cayenne Turbo, we used the latest Cayenne GTS, a lightly modified version of the standard V8 model. There are no turbochargers to help this time, only a few minor tweaks that bump its output to 420 horsepower and 380 pound-feet of torque.

And the Jeep, in this case our long-term Grand Cherokee SRT8? It doesn't look so overmatched this time around given it still has the same 470-hp V8. Then again, these are still two big and heavy SUVs, so you never know what's going to happen when they hit the track.

Vehicle: 2012 Jeep Grand Cherokee SRT8
Odometer: 1,859
Date: 5-23-2012
Driver: Chris Walton
Price: $62,880

Specifications:
Drive Type: All-wheel drive
Transmission Type: Five-speed automatic
Engine Type: Longitudinal, naturally aspirated V8
Displacement (cc/cu-in): 6,399/392
Redline (rpm): 6,200
Horsepower (hp @ rpm): 470 @ 6,000
Torque (lb-ft @ rpm): 465 @ 4,300
Brake Type (front): 15-inch vented discs with six-piston Brembo calipers
Brake Type (rear): 13.7-inch discs with four-piston Brembo calipers
Suspension Type (front): Independent double wishbones, coil springs, stabilizer bar
Suspension Type (rear): Independent multilink, coil springs, stabilizer bar
Tire Size (front): 295/45 ZR20 (110Y)
Tire Size (rear): 295/45 ZR20 (110Y)
Tire Brand: Pirelli
Tire Model: P Zero
Wheel Size: 20-by-10 inches front and rear
Tire Type: Summer performance
As tested Curb Weight (lb): 5,261

Test Results:
Acceleration
0-30 (sec): 1.7 (1.8 w/TC on)
0-45 (sec): 3.0 (3.2 w/TC on)
0-60 (sec): 4.9 (5.1 w/TC on)
0-60 with 1-ft Rollout (sec): 4.6 (4.8 w/TC on)
0-75 (sec): 7.3 (7.6 w/TC on)
1/4-Mile (sec @ mph): 13.3 @ 101.6 (13.5 @ 100.9)
Braking:
30-0 (ft): 27
60-0 (ft): 109
Handling
Slalom (mph): 67.1 ( 66.2 w/TC on)
Skid Pad Lateral acceleration (g): 0.87 ( 0.87 w/TC on )

Db @ Full Throttle: 76.4
Db @ 70 mph Cruise: 61.7

Acceleration: The Jeep punishes pedal overlap at launch, so the best technique was near-simultaneous off-brake/on-throttle. Either way, the Jeep leaps off the line and the tach swings freely up to redline and "burps" off very quick upshifts (noticeably quicker in Track mode). Sounds magnificent and burly.

Braking: These brakes like some heat for optimal performance, so the shortest stop occurred on the fifth (of seven). Medium-firm pedal, steep jump-in, minimal dive (in Track or Sport) and essentially fade-free. Remarkable for a 5,000-plus-pound SUV.

Handling:
Skid pad: With ESC off, I could steer merely with the throttle — allowing the mild understeer to come and go. Couldn't detect AWD shifting power around. With ESC on, I was much busier with the steering wheel as the electronics applied brakes and cut throttle. Resulted in same outcome.
Slalom: A little lazy with initial steering response, but takes a set immediately (in Track). Relatively little roll means it transitions quickly/predictably. With ESC off, the Jeep is essentially neutral and wants to be chucked past each cone, then becomes slightly loose. Luckily, the AWD and throttle solve this "problem." The tires allow predictable break-away at a high threshold. ESC On snubbed understeer subtly and quickly. Effective and obviously well-tuned ESC settings. Again, this is a remarkable performance for a 5,000-plus-pound SUV.

Vehicle: 2013 Porsche Cayenne GTS
Odometer: 1,626
Date: 10-16-2012
Driver: Chris Walton
Price: $125,615

Specifications:
Drive Type: Four-wheel drive
Transmission Type: Eight-speed automatic
Engine Type: V8
Displacement (cc/cu-in): 4,806/293
Redline (rpm): 6,800
Horsepower (hp @ rpm): 420 hp @ 6,500 rpm
Torque (lb-ft @ rpm): 380 lb-ft @ 3,500 rpm
Brake Type (front): 14.9-inch ventilated rotors with six-piston calipers
Brake Type (rear): 12.9-inch ventilated rotors with four-piston calipers
Suspension Type (front): Independent, dual control arms, air springs, dampers
Suspension Type (rear): Independent, multilink, air springs, dampers
Tire Size (front): 295/35R21 107Y
Tire Size (rear): 295/35R21 107Y
Tire Brand: Michelin
Tire Model: Latitude Sport
Tire Type: All-season
As tested Curb Weight (lb): 5,117

Test Results:
Acceleration
0-30 (sec): 2.2 (2.5 w/TC on)
0-45 (sec): 3.9 (4.3 w/TC on)
0-60 (sec): 6.1 (6.5 w/TC on)
0-60 with 1-ft Rollout (sec): 5.9 (6.1 w/TC on)
0-75 (sec): 8.7 (9.1 w/TC on)
1/4-Mile (sec @ mph): 14.3 @ 98.5 (14.5 @ 98.4)
Braking:
30-0 (ft): 28
60-0 (ft): 114
Handling
Slalom (mph): 67.0 ( 65.1 w/TC on)
Skid Pad Lateral acceleration (g): 0.91 ( 0.90 w/TC on )

Db @ Idle: 43.4
Db @ Full Throttle: 77.0
Db @ 70 mph Cruise: 62.5

Acceleration: Right out of the box, in all its default "Normal" modes, the Cayenne GTS doesn't feel as snappy off the line as I expected. Selecting "Sport" mode chops about a tenth off the 0-60 time and two-tenths off the quarter-mile, but we were still well shy of Porsche's claimed acceleration times. There's no launch control and it struggles to hold itself in place when overlapping the throttle and brake. Still, this 5,100-pound SUV is still pretty quick and it sounds amazing. It will hold gears all the way to redline in manual mode and it performs blazing quick rev-matched downshifts.

Braking: The PASM-equipped GTS is susceptible to pavement irregularities in "Sport" suspension mode, following every undulation and varying brake pressure accordingly. On the smooth surface, however, the brakes are exceptionally capable. Stops are flat, straight and repeatable, with no fade.

Handling:
Skid pad: Pretty mild, steady-state understeer here, but it has an amazing ability to alter course and shift weight around with the throttle. The active suspension keeps it very flat, but not in an unnatural way. Slalom: As we have seen before in previous Cayenne tests, this SUV's performance in the slalom defies logic. How Porsche manages to get this 5,100-pound SUV through the slalom with this kind of precision and poise is beyond me. Unbelievably good steering, yaw response (including with throttle), grip, and it has one of the most aggressive exits ever. This GTS matched the Turbo's performance with ease and confidence. The active suspension isn't the kind that makes me feel disconnected from the chassis at all. It just goes about its business of keeping the tires on the pavement without notice.