2015 Chevrolet Camaro Z/28 vs. Porsche 911 GT3 Comparison
Brothers in Arms: Two Racers For The Road
Let's address the $68,785 elephant out the room right now: No one is going to cross-shop these cars. Most of the folks who'll fork over $145,785 for a 2015 Porsche 911 GT3 have already owned a 911. Or two. Or three. They're not going to be tempted by a Chevy, no matter how good its Nürburgring credentials might be. The $75,000 2015 Chevrolet Camaro Z/28, on the other hand, is a white-space car. The most track-focused street-legal Camaro in history since the original COPO quarter-mile killers of the late '60s, the new Z/28 is attracting a mix of buyers, from loyalists who want the ultimate Camaro, to collectors who see a future classic, to general enthusiasts who want an affordable factory-engineered track-day car.
And that last piece is what this comparison is all about: The Z/28 and the GT3 have both been created by the best and brightest brains in the Chevrolet and Porsche engineering departments to deliver the closest thing to a race car with license plates. What we want to know is, who's done it best? And in this context, the sticker price differential between the two, while not inconsequential, is perhaps less important than how much each company is charging for all the engineering and hardware required to turn their road cars into track rats. Call it the go-fast premium.
Using the entry-level, 350-hp, $85,295 Carrera as a baseline, Porsche charges $46,100 to turn it into a GT3. Chevy charges $50,300 for the transformation of a $24,700 323-hp V-6 Camaro coupe from rental queen to a road-course warrior. However, our GT3 stickered at $145,785 thanks to the addition of a number of non-performance-enhancing options, plus the $9,210 PCCB carbon-ceramic brake package. The Z/28 comes standard with the Brembo carbon-ceramic brake package shared with the new Z06 Corvette, so with like-for-like brakes, the go-fast premium for the Porsche is $56,300. The point is, regardless of the baseline vehicle price, the upcharge for both cars is remarkably similar.
What does that money buy you? In the GT3 you get an engine that shares only its block and a handful of other components with quotidian 911s. The heads are new, and there's a new variable-length intake system to help with low-end torque and high-end power, a dry-sump oiling system, plus a new direct-injection setup that pumps fuel at much higher pressure. The pistons are forged aluminum, the rods forged titanium, and a new cam-follower system allows the whole lot to spin to a dizzying 9,000 rpm. Peak power is 475 hp at 8,250 rpm, and torque tops out at 324 lb-ft at 6,250 rpm, remarkable numbers for a 3.8-liter naturally aspirated road-car engine.
Under the Z/28's hood is the mighty 7.0-liter LS7 from the C6 Corvette Z06. Lighter than the LS3 in regular V-8-powered Camaros, this hand-built engine also features CNC-ported aluminum heads, a forged-steel crankshaft, Pankl titanium rods, Mahle forged pistons, and a dry-sump oiling system, as well as titanium valves and hydroformed headers. The engine develops 505 hp at 6,100 rpm and a healthy 481 lb-ft of torque at 4,800 rpm.
Both cars feature upgraded transmissions. The Camaro is fitted with a Tremec TR606 six-speed manual with a short-throw shifter, close-ratio gear set, and oil cooling. The GT3's version of Porsche's PDK dual-clutch transmission is lighter, has more closely packed ratios, and has been programmed to deliver even faster, more seamless shifts. The GT3 comes with continuously variable adaptive shocks, and both cars have track-specific alignments and differentials designed to distribute torque to different drive wheels during different phases of cornering.
"The GT3 is the sharpest, most precise, most buttoned-down 911 in history."
Neither the regular 911 nor the base Camaro provide an ideal baseline package for a hardcore track car. The Chevy is too big and heavy, and the Porsche's engine is in the wrong place. The Z/28 development team worked hard -- lighter engine, brakes, wheels, thinner rear glass -- but the car still weighs 3,882 pounds, a hefty 615 pounds more than the GT3, and 53 percent of that is on the front wheels. That explains the Z/28's killer app: what Chevy says are the widest and stickiest front tires ever fitted to a production car. The GT3's weight-bias problem, of course, is at the other end of the car. Porsche's killer app? Rear-wheel steering. Electric actuators steer the rear wheels in the opposite direction to the fronts at low speeds to improve agility and in the same direction at high speeds to improve stability.
Fire up the GT3, and the engine rattles like a bucket of bolts in a cement mixer until everything warms up. It might be a near-race engine, but it's wonderfully tractable and flexible and easy to drive around town. Put the PDK selector in D, and the GT3 will happily mooch down to the mall, only the firmer-than-usual ride and the giant wing bisecting the view in the mirror betraying the beast within. Switching the PDK and suspension modes to Sport, and opening up the exhaust flaps, doesn't so much unleash the beast, for there's not a perceptible change in mood, but focus it on the serious business of going fast.
The 0-60 mph sprint takes just 3.1 seconds, making the GT3 the fifth-quickest two-wheel-drive car we've tested, behind McLaren's P1 and MP4-12C, and Ferrari's 458 Italia and F430 Scuderia. The quarter mile takes just 11.3 seconds at 122.9 mph, and the figure eight is all over in just 22.8 seconds at an average of 0.96 g. Despite 157 lb-ft more torque and an extra 30 horses, the Z/28 struggles to overcome its weight handicap and is further hampered by the human factor in the transmission: No matter how hot a driver you think you are, there's no way you can match the PDK's shift speed and precision. The Z/28 hits 60 mph in 4.0 seconds and thunders down the quarter in 12.3 seconds at 116.1 mph. The figure eight takes 23.6 seconds at an average of 0.89 g.
On real-world roads, there's little separating the two, however. The GT3 is by far the sharpest, most precise, most buttoned-down 911 in history, but it still retains the elegantly fluid handling of the 991-series cars. Front-end grip is phenomenal -- there's not a trace of understeer -- and the rear-wheel-steering system neatly damps tail-end yaw motions. This GT3 feels at once agile yet remarkably neutral -- the most neutral 911 ever. And that engine! The power comes on with a smooth, elastic surge, and there always seems to be another 1,000 rpm left when you need it. Above 7,000 rpm it yowls like it was born and bred on Mulsanne Straight.
The Z/28, by contrast, is all muscle and thunder, Thor on four wheels. The LS7 is one of the all-time great Chevy small-blocks; torquey, yet free-revving, and with a delicate crispness to the throttle response its supercharged cousins can't quite match. Incredibly, the big Camaro's front end feels even more responsive than the Porsche's, thanks in part to those massive 305/30R19 Pirellis. What's more, the Z/28's steering feels more perfectly linear and more beautifully weighted than the Porsche's.
While it can hang with the GT3 on most any road, the Camaro is always a more physical, visceral drive; your right arm and left leg are busy executing gearshifts, that big V-8 bellows in your ears, and you're pounded by violent vertical body motions from bumps the light-footed Porsche skips across like a pebble skimming a lake. You're always aware the Chevy is a much bigger, wider, heavier car.
On the road the differences between the GT3 and the Z/28 seem more a matter of style. On the track they can be measured. In the hands of our resident hot shoe Randy Pobst the Z/28 turned a best lap of 1 minute, 29.72 seconds around SoCal's challenging 2.42-mile Willow Springs road course. The GT3? 1 minute, 27.22 seconds. The Porsche's lightning-quick PDK transmission helped: "I like the perfection, miss the driver involvement," Pobst said. But the traces showed the GT3 to be consistently quicker into, and through, corners, too.
"The Camaro Z/28 is all muscle and thunder, Thor on four wheels."
Pobst wasn't entirely happy with the Z/28's demeanor. "This one is loose," he said. "It doesn't have the confidence-inspiring balance I've experienced in other Z/28s." He felt the Camaro was easier on the entry into corners than the Porsche, but its rock-solid composure crumbled into uncharacteristic (and time-wasting) power oversteer on exits. The lack of grip cost the big Chevy plenty through Willow's fast, endless Turn 8. This particular Z/28 is our long-term tester, and its 60 treadwear Pirellis might have already been past their prime. We'd also taken the car to have the suspension adjusted to the recommended race settings, which might not have suited the cool track temps. In the coming months we're going to revisit the suspension settings, bolt on some fresh rubber, and find out.
That said, there's more time to be found in the Porsche, as well. "The grip is unbelievable for a street car," Pobst said after his first session in the Porsche. "Fabulous turn-in, and not a lick of understeer. But you get trailing throttle oversteer on the second half of corner entry. You have to get on the gas early to compensate." Dial out that oversteer, Pobst says, and there's easily another second to be shaved off the GT3's lap time.
"On the road the differences between the GT3 and the Z/28 seem more a matter of style."
The key point is, he's not talking hypothetically. The GT3's suspension allows for more fine adjustability than the Z/28's setup, and it's here the experienced enthusiast will always be able to find an edge over the Chevy on the track. Even with our Z/28 in top form, it's not going to catch the GT3.
If you're after a fast, rewarding, utterly exhilarating track-day car, the Camaro Z/28 is a truly unbelievable bargain. For the money you'd spend on the GT3, you could buy a Z/28, a truck and trailer to take it to the track, and have enough money left over for a few sets of tires. But the talented, sophisticated, and deeply competent GT3 shows Chevy still has a few tricks to learn when spending go-fast money to make a road-legal race car. Perhaps we shouldn't surprised -- after all, Porsche's been taking 911s to the track for more than half a century now, and the 2015 Z/28 is Chevy's first attempt at a track-rat Camaro.
And that's what excites us most. Good as this one is, the next Camaro Z/28 is going to be a helluva car. Because racing improves the breed.
Weights and Measures
Five hundred feet. All of us were surprised that the Z/28 was a whopping 1 2/3 football fields behind the GT3 when the Porsche touched the finish line. The Z/28 has 3.2 liters of extra engine displacement, 30 more hp, and substantially wider front tires. How'd that happen?
Weight is the Bow Tie's most obvious enemy, the Chevrolet's extra 615 pounds depressing its pounds-per-horsepower ratio by 12 percent compared to that of the GT3. And that -- plus being one gear short in transmission cogs -- immediately shows as they accelerate into the first corner, where the Porsche arrives traveling 8.2 mph faster as they grab their brakes.
The pattern is repeated on each straight, but the GT3 has other tricks, too: Notice how it doesn't brake nearly as much before twisting into corners 2 and 9. With its 40-percent front, 60-percent rear weight distribution, the Porsche is better balanced under braking to incrementally add cornering g's to both axles. Lastly, notice how driver Randy Pobst uncharacteristically slows his shift in the Camaro at Turn 6. Why? It's right where a small hill suddenly falls away beneath you -- not a good place to unload the Z/28's prodigious V-8 torque. Does the Porsche's advantage arise from magic? No. There's nothing more up its sleeve than highly trained muscle.
|2015 Chevrolet Camaro Z/28||2015 Porsche 911 GT3|
|DRIVETRAIN LAYOUT||Front-engine, RWD||Rear-engine, RWD|
|ENGINE TYPE||90-deg V-8, aluminum block/heads||Flat-6, alum block/heads|
|VALVETRAIN||OHV, 2 valves/cyl||DOHC, 4 valves/cyl|
|DISPLACEMENT||427.6 cu in/7,008 cc||231.9 cu in/3,800 cc|
|POWER (SAE NET)||505 hp* @ 6,100 rpm||475 hp @ 8,250 rpm|
|TORQUE (SAE NET)||481 lb-ft* @ 4,800 rpm||324 lb-ft @ 6,250 rpm|
|REDLINE||7,000 rpm||9,000 rpm|
|WEIGHT TO POWER||7.7 lb/hp||6.9 lb/hp|
|TRANSMISSION||6-speed manual||7-speed twin-clutch auto|
|SUSPENSION, FRONT; REAR||Struts, coil springs, anti-roll bar; multilink, coil springs, anti-roll bar||Struts, coil springs, adj shocks, anti-roll bar; multi-link, coil springs, adj shocks, anti-roll bar|
|BRAKES, F;R||15.5-in vented, drilled, carbon-ceramic disc; 15.3-in vented, drilled, carbon-ceramic disc, ABS||16.1-in vented, drilled carbon-ceramic disc; 15.4-in vented, drilled carbon-ceramic disc, ABS|
|WHEELS, F;R||11.0 x 19-in; 11.5 x 19-in, forged aluminum||9.0 x 20-in; 12.0 x 20-in forged aluminum|
|TIRES, F;R||305/30R19 102Y Pirelli P Zero Trofeo R||245/35R20 91Y; 305/30R20 105Y Michelin Pilot Sport Cup 2|
|WHEELBASE||112.3 in||96.5 in|
|TRACK, F/R||66.1/64.7 in||61.0/61.2 in|
|LENGTH x WIDTH x HEIGHT||192.3 x 76.9 x 52.4 in||178.9 x 72.9 x 50.0 in|
|TURNING CIRCLE||39.0 ft||36.4 ft|
|CURB WEIGHT||3,882 lb||3,267 lb|
|WEIGHT DIST., F/R||53/47%||40/60%|
|HEADROOM, F/R||37.4/35.3 in||37.8/- in|
|LEGROOM, F/R||42.4/29.9 in||66.7/- in|
|SHOULDER ROOM, F/R||56.9/42.5 in||53.4/- in|
|CARGO VOLUME||11.3 cu ft||4.4 (fr) 9.2 (rr) cu ft|
|ACCELERATION TO MPH|
|0-30||1.6 sec||1.2 sec|
|PASSING, 45-65 MPH||1.8||1.5|
|QUARTER MILE||12.3 sec @ 116.1 mph||11.3 sec @ 122.9 mph|
|BRAKING, 60-0 MPH||100 ft||98 ft|
|LATERAL ACCELERATION||1.08 g (avg)||1.11 g (avg)|
|MT FIGURE EIGHT||23.6 sec @ 0.89 g (avg)||22.8 sec @ 0.96 g (avg)|
|2.42-MI ROAD COURSE LAP||89.72 sec||87.22 sec|
|TOP-GEAR REVS @ 60 MPH||1,500 rpm||2,500 rpm|
|PRICE AS TESTED||$76,150||$145,785|
|AIRBAGS||Dual front, front side, f/r rear curtain||Dual front, front side, front head|
|BASIC WARRANTY||3 yrs/36,000 miles||4 yrs/50,000 miles|
|POWERTRAIN WARRANTY||5 yrs/100,000 miles||4 yrs/50,000 miles|
|ROADSIDE ASSISTANCE||5 yrs/100,000 miles||4 yrs/50,000 miles|
|FUEL CAPACITY||19.0 gal||16.9 gal|
|EPA CITY/HWY/COMB ECON||13/19/15 mpg||15/20/17 mpg|
|ENERGY CONS., CITY/HWY||259/177 kW-hrs/100 miles||225/169 kW-hrs/100 miles|
|CO2 EMISSIONS, COMB||1.28 lb/mile||1.15 lb/mile|
|RECOMMENDED FUEL||Unleaded premium||Unleaded premium|