INDYCAR: Inside The 2012 Dallara

IndyCar

INDYCAR: Inside The 2012 Dallara

Marshall Pruett takes you inside the the new 2012 Dallara Indy car.

Marshall Pruett | Posted August 13, 2011

The current Dallara IR07, bottom, will be replaced by radically different IR12 next year. (LAT)

Its styling is somewhat polarizing, but beneath the skin--and even for the parts that are exposed, the new 2012 Dallara Indy car is an entirely different creature to what fans have grown accustomed to.

Born from the decisions made by the ICONIC (Innovative, Competitive, Open-Wheel, New, Industry-Relevant, Cost-Effective) IZOD IndyCar Series Advisory Committee in 2010, teams will compete next year with the first brand-new design since the Indy Racing League (IRL) introduced its original formula for the 1997 season.

A throng of vendors and officials took part in the Dallara IR12's first test at Mid-Ohio on August 8-9. (LAT)

Utilizing bespoke chassis from Dallara, GForce and Riley & Scott, and 4.0-liter, naturally-aspirated V8 engines from General Motors and Nissan, the first-generation IRL cars followed a design and cost philosophy that was fundamentally different than almost every aspect of formula used by the rival Championship Auto Racing Teams (CART) series.

At a time when 7- and 8-figure annual budgets were the norm in the technology-friendly CART paddock--thanks to extreme spending by multiple engine manufacturers, high-tech turbocharged engines and a healthy sponsorship base--the IRL went in the opposite direction, opting for relatively simple spec cars, minimal technology and non-turbo, production-based engines.

15 years later, the second-generation IRL-turned-IndyCar Series formula will deliver an interesting compromise between the open-wheel identities forged by CART and Champ Car, and the 1997-era IRL machines.

WHAT'S DIFFERENT?

If the current 2007-spec Dallara ‘IR07’ chassis is a heavyweight, INDYCAR and its partners at Dallara set out to drop the 2012 car down one weight class—something closer to a light-heavyweight. This is a rather unique step for the series and American open-wheel racing in general.

Aerodynamically, the 2012 Dallara ‘IR12’ chassis, which has been referred to as the ‘IndyCar Safety Cell’ by the series, has been designed using the principles found in CART/Champ Car. Where the IR07 makes use of a flat-bottom floor and large wings to make its downforce, the IR12 features venturi tunnels—'ground effects,' to some—to generate most of its downforce below and less aggressive wings on the top.

The basic changes, and difference in wheelbase become apparent when the two Dallaras are overlaid. (LAT)

In the engine bay, the ICONIC panel elected to move away from the 3.5-liter V8 formula in favor of smaller, lighter and more commercially appealing 2.2-liter turbocharged engines.

CART/Champ Car became synonymous with the 2.65-liter single-turbo V8 engine layout, and while the 2012 IndyCar rules are similar in many ways, the capacity has been reduced, a maximum of six cylinders are allowed and manufacturers can choose between single- or twin-turbo layouts.

The last major change for the IR12 can be found within the cockpit. Dallara and the IndyCar Series made a considerable effort to provide more space for drivers of all sizes.

From losing weight to making its downforce in a different manner to producing power with the aid of forced induction, an exciting change is on the horizon for IndyCar teams, drivers and manufacturers.

Let’s look at the major (and minor) changes in greater detail:

CHASSIS

From the outside, the IR07 and IR12 bear little resemblance, but dimensionally, the two Italian Indy cars are very similar.

Comparing the cars in road course trim, the IR07 raced at Mid-Ohio last weekend with a wheelbase of roughly 122 inches. Teams were once allowed to vary wheelbase by quite a bit, but in recent years, 118-122 inches has been the allowable range. The IR12 will ship with a fixed wheel base of 120 inches that will be used at all times.

At the behest of the series, Dallara designed the IR12’s body to reduce the likelihood of wheels becoming interlocked, which can be seen in a few key areas.

Looking at the car from the front or overhead, one unique solution stands out—literally.

Two-time Indy 500 winner Dan Wheldon raved about the space inside the cockpit, noting the considerable space for longer legs as seen between the steering wheel and dash bulkhead. (LAT)

While the IR07’s track width must fall between 77.5-78.5 inches and is wider than the bodywork, the IR12's track width is slightly narrower at 76 inches, yet has bodywork—specifically, the floor—that measures 79 inches wide.

That translates into a 1.5-inch bodywork protrusion on the IR12, and means that in drivers will be lucky to get away without damage if they hit the wall or another car flush on either side.

With the narrower track, the front wheels are more protected by the front wings, and the front wing endplates have carbon pieces that extend out to block a portion of the front tires. Behind the front tires, the floor is used to prohibit wheel interlocking by filling some of the void between the tire, chassis and sidepod.

The yet-to-be-named anti-interlocking structures affixed behind the rear tires form part of the IR12’s new rear impact unit. A new rear crash attenuator is used, and at the bottom rear of the device, a robust beam is attached that extends outwards to both wheels. The anti-interlocking units bolt to each end of the beam through six fasteners apiece, forming a rigid assembly.

Some weight has been saved with the new chassis by integrating the anti-intrusion panels—heavy steel items that were added the exterior of the IR07 to protect its drivers—into the monocoque, but overall, the quest to ship the IR12 at the stated goal of 1380 pounds, a weight savings of 185 pounds over the IR07, is an ongoing effort.

Members from INDYCAR and Dallara confirmed that meeting the target weight will be a challenge, and due to having a number of prototype parts fitted to the IR12, they would not be drawn on weight distribution figures or an anticipated final curb weight.

The cockpit itself received an extensive redesign, and IR12 test driver Dan Wheldon told SPEED.com just how cavernous it felt in comparison to the IR07 he drove to victory at the Indy 500 in May.

“I think they’ve made huge gains from a safety standpoint,” he said. “It’s very different to the cockpit we have now. With the [IR07], the position you sit [in] has you as low as possibly can, below the airbox, but when you sit that low your legs are ride over the fire bottle, and then you go back down and kind of sit lower; it’s just not very fluid. You’re compacted a bit. The new seating position is very fluid, there’s a lot more seat around you; the vision is very good.

The IR12's underwing sticks out past the wheels to discourage wheels from becoming interlocked. (LAT)

"Honestly, you just feel so much safer with all of the extra space around you. You’ve got less stuff around you—around your feet, so it’s really modern in that way.”

The cockpit of the IR12 is longer and wider than the IR07, with the driver moved farther back between the axle centerlines, allowing for more legroom if needed. Elbow room is a comfort most IndyCar drivers have gone without for many years, but the IR12 addresses that issue as well, and can accommodate wider shoulders.

Ingress and egress is improved with the longer cockpit aperture, according to Wheldon.

“I slipped right into the car and it felt good immediately. It felt real good from all angles. You can pull your knees back and it doesn’t have the sensation like the [IR07] has with the dash being close and the [cockpit] sides crowding in a bit.”

Page 1 of 3

12 3