Cadillac ATS, light from the start, performance above all

Cadillac has a clear target in mind for the upcoming Cadillac ATS: to handle and perform better than a BMW 3-series. In order to achieve that goal they are designing a new platform from the ground-up, selecting appropriate materials, and the right power trains. If they are successful, the Cadillac ATS will be the new benchmark for luxury performance.

Engineers look over the all-new Cadillac ATS before performance tests at Atlanta Motorsports Park Tuesday, May 8, 2012 in Dawsonville, Georgia. The Cadillac ATS is engineered to be the lightest compact luxury sports sedan, reducing weight through the use of advanced materials - but not at the expense of performance. (Photo by Sam Sharpe for Cadillac)

DETROIT – When engineers set out to make the all-new 2013 Cadillac ATS as light as possible they used advanced materials to minimize weight throughout the compact luxury sports sedan but never compromised performance capability.

Lightweight parts such as an aluminum hood and magnesium engine mounts help ATS achieve a curb weight less than 3,400 pounds, and highway fuel economy well over 30 mpg. Keeping weight down also enabled balanced distribution of vehicle weight that helps delivers a world-class driving experience.

“We designed and engineered ATS’s vehicle architecture to deliver quick, nimble and fun-to-drive dynamics,” said David Masch, ATS chief engineer. “We distributed mass to key areas, much like an athlete builds muscle where he needs it most. This enabled ATS to achieve the performance characteristics that luxury sport sedan buyers demand.”

One seemingly heavy way the ATS engineering team achieved its performance goals was using cast iron in the rear differential instead of aluminum, a learning taken from the performance-tuned CTS-V.

The differential provides torque and rotation to the wheels, and ATS’s cast iron design helped distribute weight equally between the front and rear wheels to provide agile handling while reducing noise and vibration. Cadillac benchmarked it against world-class competition to deliver a driving experience that is as well-tuned for sound as for ride and handling.

Unlike a differential made from aluminum, which expands and contracts twice as much in response to temperature change, a cast iron differential is stronger and retains its shape better under temperature extremes, which allows the ring and pinion gears to operate more quietly. As a result, a cast iron differential also requires less energy to operate, contributing to higher fuel efficiency. To the consumer, this means more miles between fill-ups.

The ATS team also achieved significant weight reduction in the rear suspension by using specially engineered straight steel links with lightening holes instead of using aluminum.

“The team focused on grams, not pounds, every day of the ATS’s development,” Masch said. “Even the smallest of changes could contribute to the overall mass goal.”

ATS’s wheels also benefited from 50-50 mass distribution between the front and rear. While heavier cars need larger wheels, tires and brakes to account for heavier mass, ATS’s relative light weight enabled the use of optimized high-strength aluminum wheel forgings and Brembo brakes that deliver stopping distance of approximately 129 feet decelerating from 60-0 mph, which is expected to be best in the segment.

Inside the ATS, the vehicle team took advantage of a new process that places sound-absorbing material between two layers of laminated steel. By doing so, Cadillac refined a part and process it pioneered on CTS.

These sound-buffering materials help reduce noise coming into the cabin from the powertrain and fine-tune the sound to a sporty growl that communicates powertrain response and road characteristics to the driver.

ATS also uses an acoustically laminated windshield and side windows that are lighter than standard tempered glass and provide better wind and powertrain noise reduction for a quieter interior. Acoustically laminated glass also offers almost double the amount of ultraviolet ray protection.

“Smart material selection and styling modifications that reduce complexity are key enablers in our quest to reduce vehicle mass,” said Bob Boniface, Cadillac exterior design director, who spoke Thursday during a panel discussion on lightweighting at the Automotive Press Association.

“As consumer demand for more features, space and comfort continues to increase, so too has our proficiency in designing vehicles that offer aerodynamic performance and efficiency equivalent to lower vehicle weight,” he said.

The ATS, which starts at $33,990, goes on sale this summer.

Final Cadillac ATS power figures?

The Cadillac Dealer Order Guide is online and although the ATS info still seems pretty preliminary, it shows the initial figures for the Cadillac ATS power trains:

LCV Engine, 2.5L I4, DI, DOHC, VVT (202 hp [150.6 kW] @ 6300 rpm, 190.3 lb-ft of torque [258 N-m] @ 4400 rpm)
LTG Engine, 2.0L Turbo, I4, DI, DOHC, VVT (272 hp [202.8 kW] @ 5500 rpm, 260 lb-ft of torque [353 N-m] @ 1700-5500 rpm)
LFX Engine, 3.6L V6, DI, DOHC, VVT (321 hp [239.4 kW] @ 6800 rpm, 274.4 lb-ft of torque [372 N-m] @ 4800 rpm)
  • 2.5L Four cylinder LCV: The new standard equipment ATS will get the new 202 hp inline 2.5L four cylinder.  It wasn’t that long ago that the 4.9L OHV Cadillac V8 was rated at 200 hp, and that Cadillac weighed more than the ATS will.  The 2.5L ATS should have plenty of power.
  • 2L Turbo Four LTG: The LTG 2L turbo was spec’d at 270 hp but has settled up to 272 hp.  This is likely to be the surprisingly balanced choice for an overall package, and offer a lot of room for upgrades and modifications.
  • 3.6L Six LFX: The Cadillac ATS LFX 3.6L variant gets a Camaro-like 321 hp.  This is a good selection, as it could have been the 304 hp flex-fuel variant or the 318 hp version from the CTS.  Out of the box this will be the ‘hot’ choice for the ATS.

The planned wheels are 17″ and 18″ wheels which are ideal for weight and performance.  This also highlights the choice of tires:

RB7
Tires, P225/40ZR18 all-season, blackwall
QFN
Tires, P225/40R18 front and P255/35R18 rear, 90W blackwall RF4

The 17″ wheels will have 225/40 tires, and the 18″ will sport staggered 225/40 and 255/35 tires.

Some packages will include steering wheel-mounted Magnesium paddle shifters for the automatic, so no matter which transmission  you choose there will be complete control over gear selection.

Cadillac Signature Styling Enhances ATS Performance

Hundreds of testing hours in wind tunnel helps reduce drag, wind noise

DETROIT — The 2013 Cadillac ATS’s all-new vehicle architecture provided Cadillac designers with the unique opportunity to tailor the compact luxury sedan’s styling and refinement cues to improve driving performance. This aspect of the ATS’s development is highlighted in the fifth chapter of a YouTube video series.

“The primary function of the ATS is to be a driver’s car, fun to drive, nimble and quick,” said Bob Boniface, Cadillac exterior design director. “It has a great powertrain, great chassis, so we wanted the exterior design to reinforce that message. We worked very closely with Engineering to ensure our design met all of the performance metrics they had set out.”

A long, 109.3-inch (2,775 mm) wheelbase and wide front/rear tracks are the cornerstones of the ATS’s firmly planted stance, which is enhanced by short overhangs and taut sheet metal that appears to wrap tightly around the tires.

Cadillac’s prominent shield grille is more agile and athletic, featuring active grille shutters that close at certain highway speeds to reduce aerodynamic drag and enhance fuel economy. The center, high mounted stop light (CHMSL) on the rear decklid provides downforce to improve aerodynamic performance.

“When you start a new program, a new architecture, it’s much different than re-skinning something else. The opportunity is both challenging and rewarding,” said Taki Karras, Cadillac ATS exterior design manager. “The ATS has a lot of gesture in the line work and that leads to the overall performance nature.”

The ATS’s clay models and full sheet metal models spent hundreds of hours in wind tunnel testing to reduce wind noise and drag, improve air flow and performance and enhance fuel economy.

A driver-focused interior with integrated technology and crafted materials complements the exterior elements and supports the ATS’s driving experience. Everything from the placement of the pedals to the position of the shifter is designed for effortless and intuitive performance driving. Available performance seats have power-adjustable bolsters to optimize lateral support during high-load cornering

“I think what will surprise people most when they get in the ATS is we’ve given them a beautiful driving environment with plenty of space in what seems like a small exterior,” said Eric Clough, Cadillac interior design director.

Contributing to the interior’s intuitive feel is an instrument panel that wraps into the doors and a center stack in the mid-instrument panel that flows into the center console. LED lighting for the bold gauge cluster enables clear, at-a-glance viewing in all lighting conditions, while ambient lighting accents functional elements of the console and doors.

“When you drive this car, its combination of design, powertrain and engineering and interior design. It’s the entire package,” Boniface said. “This isn’t just another car, it’s a Cadillac.”