Chevy Notes for Pikes Peak IRL
BOWTIE BULLET POINTS: Chevrolet Notes for the Honda Indy 225
Pikes Peak International Raceway
Round 12 of 16, Indy Racing League IndyCar Series
Sunday, August 22, 3:45 p.m. EDT
TV: ABC (live), 3:30 p.m. EDT
* Into Thin Air
The IRL IndyCar Series will head for the hills for Sunday's Honda Indy
225 at Pikes Peak International Raceway near Colorado Springs, Colo.
Nestled in the Front Range of the Rocky Mountains, PPIR literally stands
above the other circuits on the IRL tour at an elevation of 5,357 feet. The
high-altitude oval requires adjustments in the engine and chassis
specifications to compensate for the thin air at more than a mile above sea
level.
The naturally aspirated engines used in the IRL IndyCar Series depend
on atmospheric pressure - the force produced by the weight of the
Earth's atmosphere - to fill their cylinders with fuel and air. Standard
atmospheric pressure is 14.7 pounds per square inch (psi) at sea level, but
at PPIR the pressure is typically around 12.2 psi. This "rare air" reduces
engine output significantly.
"This weekend's race is the first time that we will run the
3.0-liter version of the Chevy Indy V-8 at a high-altitude track," said Joe
Negri, GM Racing IRL program manager. "Pikes Peak International Raceway is
a unique facility, and we'll go there with an engine combination that we
use only once a year.
"Any naturally aspirated engine loses power in proportion to the
reduction in atmospheric pressure," Negri explained. "The lower air density
at high altitude reduces the oxygen that is available for combustion and
therefore decreases horsepower. Reliability is typically very good at PPIR
because the engines are operating well below their maximum output.
"Even though we will experience a significant reduction in power
at altitude, the cars still run exceptionally fast at PPIR because there is
less aerodynamic drag. And since the engines don't make as much power, we
expect fuel economy to be higher than at equivalent 1-mile tracks. That
could have an impact on the teams' race strategies."
* The Air Force
The lower air density at the mile-high PPIR oval also affects the
race cars' aerodynamics and cooling. The wings and underbody venturis
produce less downforce and drag at altitude, and the thinner air is less
effective in removing heat from the radiators. GM Racing engineers, working
with Chevrolet IRL teams, make adjustments in engine systems and
aerodynamic packages to compensate for the unique conditions encountered at
PPIR.
"The air density at Pikes Peak International Raceway is about 80
percent of normal, so the IRL race cars lose about 20 percent of their
downforce compared to sea-level conditions," said Kevin Bayless, GM
Racing's aerodynamics and chassis specialist. "Although the IndyCar Series
introduced a new aero package, the setups won't be radically different from
previous years. The 10-degree banking at Pikes Peak helps to counteract the
loss of aerodynamic downforce, and the fast drivers will probably be able
to run flat out in qualifying. For the race, however, the teams would
normally add a couple hundred pounds of downforce. That becomes difficult
at PPIR because the changes you would make at a sea-level track aren't as
effective because of the thinner air.
"Along with less horsepower and less downforce, there is also less
cooling efficiency," Bayless noted. "That's because there is approximately
20 percent less air flowing through the coolers to dissipate heat. The
openings in the sidepods that supply air to the radiator must be opened up
in order to achieve adequate cooling capacity."
* Pikes Peak Revisited
GM engines have won six of the eight IRL events contested at Pikes
Peak International Raceway. GM's roster of winners includes Tony Stewart in
1997, Kenny Brack in 1998, Greg Ray in June and August 1999, Buddy Lazier
in 2001 and Gil de Ferran in 2002. GM drivers have started on the pole
seven times at PPIR. Ray set the PPIR qualifying speed record at 179.874
mph on June 17, 2000, driving Team Menard's Indy car powered by a 3.5-liter
IRL Aurora V8 engine.
* Chevrolet Drivers on Pikes Peak International Raceway
ALEX BARRON, Red Bull Cheever Racing Chevrolet Dallara:
"Having not raced there for a while, my only memories of Pikes Peak are
of the big hail storm there in 2002. Due to the high altitude, there is a
lack of downforce, but Pikes Peak is one of the better tracks that we race
on because of there is a lot of passing."
TOWNSEND BELL, Panther Racing Menards/Johns Manville Chevrolet Dallara:
"I'm excited about getting to Colorado Springs and racing at Pikes
Peak. We're still frustrated that things didn't turn out right in Kentucky,
but everybody has moved on and turned their focus to getting it right
this weekend. I think we've taken some huge steps in our five races
together. Johns Manville is headquartered in Denver, so I'm excited about
meeting some people from there and putting on a show for them at the race
on Sunday."
ED CARPENTER, Red Bull Cheever Racing Chevrolet Dallara:
"I've raced at Pikes Peak quite a bit when I raced in USAC. It's always
a unique track to run with the high altitude, due to the lack of downforce
and the way the engine runs. I'm looking forward to getting back on the
track and keeping my momentum going."
FELIPE GIAFFONE, Team Purex Dreyer & Reinbold Chevrolet Dallara:
"I'm looking forward to getting back to a 1-mile oval. I love going
back there because it's a fairly smooth track, plus it's a great city, with
so many things to do. I've had good qualification runs there, but it's very
tricky to find the setup to last the entire race. I remember in the past
I've been fast for a few laps, but then the track changed a lot during the
race. It should be interesting as a two-day event because everyone is going
to have to sort things out very fast."
TOMAS SCHECKTER, Panther Racing Pennzoil Chevrolet Dallara:
"I was able to run very well at Pikes Peak last year. We had a good
car and a good race, and I remember that the Pennzoil Panther car was very
good there, as well. The Panther team has given me great race cars all year
long, and I'm sure they will again this weekend. I'm really looking forward
to racing in Colorado. It's always an exciting race."
* Racing Across America
Chevrolet will be represented in five major motorsports series
this weekend. While six Chevy-powered Indy cars compete at Pikes Peak
International Raceway, Chevrolet Monte Carlo coupes will race in the NASCAR
Nextel Cup and Busch Series events at Michigan International Speedway.
Chevy drag racers will put their Monte Carlo Funny Cars and Pro Stock
Cavaliers through their paces in NHRA competition in Memphis, Tenn., and
the Corvette Racing team will aim for its eighth straight victory in the
American Le Mans Series at Elkhart Lake, Wis. Chevrolet is the only
manufacturer that currently competes in America's premier stock car,
open-wheel, drag racing and road racing series.
