CHEVY, HONDA TEST 2012 DALLARA AT FONTANA

By: Marshall Pruett
November 29, 2011
Chevrolet and Honda take their 2012 Dallaras to Auto Club Speedway's two-mile oval in search of speed and information with the new IndyCar package.
The latest round of track testing by Chevrolet and Honda began on Tuesday as IndyCar’s most active engine manufacturers took to the two-mile Auto Club Speedway oval.
With Team Penske’s Ryan Briscoe getting his first taste of the Chevrolet-powered Dallara chassis, and with Target Chip Ganassi Racing’s Scott Dixon sampling the Dallara-Honda for the first time on an oval, the Aussie and Kiwi came away with decidedly different opinions after completing the first of a two-day test.
“To be honest, I thought the program ran pretty well today,” said Briscoe. “For my first feeling with the car, it ran well, we got a balance which felt pretty good and we ran speeds which were pretty close to what we would expect to run with the old car. And we haven’t even found the limit.”
For Dixon, who recently tested Honda’s DW12 at the Mid-Ohio road course, it was his turn to experience all of the handling problems his teammate Dario Franchitti encountered at Indy.
"The learning curve with this car is much steeper on the ovals than on the road courses,” he told SPEED’s Robin Miller.
“It was pretty decent right out of the box the first time I drove it on a road course but today, well, it's been a long process. We're scratching our heads about what the car needs and right now we're way out of the box. It's frustrating but at the same time kind of interesting because we have to re-learn the car. But a couple of key areas need work. We've got a ways to go and it's a bit of a pig at the moment."
Previous oval tests with Franchitti, Tony Kanaan and Dan Wheldon drew complaints of a severely loose car entering the corner, followed by the DW12 then heading for the wall on corner exit.
The gentle turns at the ACS oval are nothing like the sharp angles drivers deal with at Indy, but Dixon says despite the less demanding corners on the southern California oval, the same handling problems appeared.
"Yeah, it's evil on entry, not sure about what to say in the middle [of the corner] and then it pushes like crazy. It's just nasty getting in; an ill feeling, and I had two or three big moments today. With most cars you can anticipate what's coming, but with this car, you're not sure what to expect. We were far from trimmed out, [but] had to put most of the downforce back in. But the way it is now it's not going to be easy-flat, I can promise you that."
Farther down pit lane, Briscoe says the Chevy camp found their DW12 to be far more stable and predictable.
“After following the Indy tests where speeds were down from what people were expecting, things were pleasantly surprising today. Better than expected based on what we’d heard. It’s not all that bad, but [Auto Club Speedway] is the only place I’ve driven it. It’s not difficult to find a good balance on a big two-mile oval. I don’t know what setups they ran on the Ganassi car; maybe it’s a setup thing, but my car didn’t feel that evil today. It had a bit of push off [of the corners], but it was curable.”
For all of the differences reported by the two pilots, and with what appears to be differing philosophies on engineering the DW12, Briscoe and Dixon still managed to lap at similar speeds, running between 215-220 mph on a day that was graced with calm skies.
With the well-documented problems facing the DW12, some arrived at the track expecting to work through an articulated action plan on behalf of INDYCAR.
The majority of those plans to address the DW12’s rear weight bias, as teams learned, would be held for the next round of manufacturer testing, which allowed Briscoe and Dixon to dive into testing 2012 tires for Firestone and trying different levels of downforce.
“The main thing we did today other than tire testing was trying downforce changes—adding downforce, taking it away, adding drag to make the car more difficult to drive—and running through the downforce sweeps to get a better feel for the car,” Briscoe explained.
“We’re certainly not done; we’ll do more [Wednesday] but I’d say we learned a lot already. I don’t think we’ve gotten to the ideal place with the car yet, like you’d want to go out and qualify, which is promising. There’s definitely still more to get out of the car.”
Of the data the two test teams generated for INDYCAR, Briscoe and Dixon helped to generate info on possible downforce and drag levels for the series to consider using at the other ovals they'll visit.
“We’ve got to figure out the aero formula we’re going to use for a lot of these tracks we’re going to,” said Dixon. “We tried a lot of different aero pieces and configurations; some tracks will need different things than others. We probably changed a differential of 400 pounds of downforce throughout the day and we didn’t even get to any tire testing.”
The Chevrolet team, as Briscoe shares, completed a similar downforce/drag level program of its own on Tuesday.
“This is about testing the different downforce levels for the ovals we’ll go to next year so we can get rid of ‘pack racing,’ and we all know what a problem that is, and then the series can start to decide what downforce it wants at those tracks so they can put that into the rules," he said. "We didn’t do any setup work beyond the aero balance stuff, and the mechanical side wasn’t bad.”
Briscoe also got to experience a turbocharged Indy car engine for the first time since 2006 when he did two races in the Champ Car series.
“My first impression was that we had some turbo lag at low rpms, which isn’t really a problem at this track,” he said. “You just need to get your revs up leaving the pit box. The turbo felt kinda’ cool and weird. If you run around on the apron, you can go from half-throttle to full-throttle and it won’t step out, but once you hit full-throttle, the thing really accelerates—just what a turbo does.”
The engine manufacturers were asked to provide more power for the test at ACS, and according to one of the camps, it did not result in the straight-line speed improvement that was expected, which would point to excessive drag continuing to limit the car’s top speed.
Of the noticeable aerodynamic changes to the DW12 at Fontana, both cars were fitted with updated floors. Featuring flow conditioners behind the front tires, the new pieces, according to Briscoe, serve as more of a safety device than an aerodynamic aid.
“The new piece on the floor is a safety item more than a performance item—it’s a bit of a barrier to keep wheels from getting into that area in side-by-side racing. It’s meant to prevent tire-to-tire contact and car’s launching. If anything it might reduce drag a little bit.”
While the DW12s did not show any marked increases in top speed as a result of the revised floor, it’s believed greater drag reductions can be found by concentrating on the open area behind the front wheels.
After a rough first day on the ACS oval, Dixon added himself to the list of drivers who want to see major changes to the handling traits of the DW12.
"We need to get the weight forward to get rid of the pendulum feeling and there are so many things we need to find,” he said. “I guess the easiest thing would be to move the suspension back but I don't think Dallara is keen to do that.”
The fixes the Italian constructor has come up with will be pressed into service next month, as Dixon explains.
“From my understanding, the weight [reduction] stuff--the revised customer gearbox with the lighter spool and stuff--is now going to be ready for testing at Homestead. And some of the [high-density ballast] they want to add to the front will also be tested there.”
With veteran drivers and teams offering input on how to fix the DW12, opinions will continue to vary on the best paths to take. Whether it’s altering the wheelbase through new a-arms, reducing weight at the back of the car, adding weight to the front of the car or a combination of all three, solving the car’s rear weight bias problem will have to wait until mid-December.
And with a limited number of new aero parts to try at ACS, answers on how to shed the DW12’s excess drag in Speedway trim will also have to wait for a later date.
Until those testing results are known, and based upon what he witnessed on Tuesday, the ever-positive Briscoe will remain optimistic about the car's future.
“Everyone is focused on finding solutions and is being really open-minded about working together to make that happen,” he said. “I feel confident we’ll get to next season and we’ll have a good product to offer. The testing moves over to Homestead next which is more of a handling circuit, and so there I think they’ll be focusing more on the balance of the car. You can’t do a lot of that here.
“Yeah, you can feel the rearward weight bias at the moment, but it doesn’t hurt you so much at a track like this. You set the aero up to where it needs to be and change the springs a little bit, and you find yourself with a good racecar. Go to where you’re pulling tighter corners like Homestead and that’s where I think you’ll see the new updates will make a bigger difference.”
The topic of differing oval setups is also worth monitoring.
No one questions the need to correct the DW12's weight distribution, but the fact that Briscoe and Dixon--two of the most skilled oval drivers in the series--are reporting such different things about the handling of their respective DW12s is rather fascinating.
Dixon didn't bother trying to hide his frustration at the end of Tuesday, while Briscoe simply couldn't related to most of what the Honda team was experiencing.
It's entirely possible that with the weight distribution issues and drag problems they've encountered, the Ganassi-led Honda program and Team Penske- and KV Racing-led Chevrolet program have arrived at completely different ends of the setup spectrum while seeking solutions.
More will be known in the coming weeks as both manufacturers continue to develop their cars and engines.
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