May 18, 2007
By: John Stahmann
The American Le Mans Series introduced a new program for the 2007 racing season which they have aptly labled “Vitesse”. Vitesse is a French word meaning “the speed at which something happens…” and the goal of the Vitesse program is to demonstrate the relevance between American Le Mans Series manufacturer’s race entries and the vehicles these same manufacturers make available to everyday consumers.
Both Audi and Chevrolet have teamed up with the ALMS to demonstrate just how much their street cars have benefitted from each brand’s race program. Chevrolet is of course utilizing its Corvette Z06.
For Vitesse Audi is demonstrating its technology through not just one, but two vehicles – a purpose-built Audi RS4 Speed Challenge race car and the superlative Audi R8 sportscar. Champion Motorsport built an RS4 race car with the specific intentions of campaigning the vehicle in the 2007 Speed World Challenge Series. When the car was nearing completion various factors led Champion to the unfortunate decision not to race with it this year. The good news was that the vehicle was still fully built out.
The result is a purebred race car built on the Audi RS4 platform but without a mandate. Audi subsequently decided to utilize the car to showcase its race technology and give the public a a closer look at the blurred line between race and road technology.
Some details about the RS4 Challenge car:
- The engine is a stock RS4 engine with identical internals to the RS4 available from Audi dealerships – even running a stock airbox and air filter
- The engine management system has been modified
- The exhaust system is comprised of custom built headers and straight pipes; there are no catalytic converters and no mufflers
- Engine output is rated at around 500 hp
- The transmission has been modified with custom gears and has been both reinforced and lightened
- Doors, trunklid, bumpers, b-pillars, door handles, and dash are all carbon fiber
- Front doors weigh 2 kilos (4.4 lbs) each
- The suspension has been modified for race and uses custom Ohlin components
- The braking system has also been race-modified and utilizes Alcon brake components
- The car weighs approximately 2900 lbs
Walking around the RS4 Challenge, we immediately noticed the not-so-subtle touches like the rear wing and red mirror covers. The front wheels have a very agressive alignment camber, and the race car is running 18″ wheels shod with 265 rubber as opposed to the standard 19″ wheels and 255 rubber. Looking around the car there is carbon fiber pretty much everywhere – the door pulls, the b-pillars, and especially on the interior where the dash, doors, and other interior surfaces stand out.
We enter the RS4 Challenge and from the start we know that this is not just an RS4 with racing seats. No, this is a fully developed race car that just happens to have two seats in it. After meeting our driver and strapping into the car we took off for a lap around Miller Motorsports Park.
Being intimately familiar with this track we can profess that the RS4 Challenge car has amazing power and handling capabilities. Although we’ve also taken the 23 turn, 4.5 mile course in a Speed Challenge GT3 cup car, the RS4 felt much more balanced, more planted and certainly appeared easier to handle for the driver.
The sheer power of the 4.2-liter engine and the amazing cornering forces handled by the car can only be summed up in one word – brutal. In fact, the rumor is that a journalist who rode in the car earlier in the season actually wet his pants! Turn after turn the RS4 Challenge proved amazingly sticky and with seemingly unlimited acceleration. As we came out of turn 23 at Miller in a four wheel slide, we couldn’t help but be a little sad that it had all gone by so quickly.
After exiting the RS4 challenge car next up was the same course in the R8. Riding in the R8 after the RS4 Challenge car was an eye-opening experience. Compared to the RS4 Challenge car the R8 was obviously much more refined, but the R8 had very similar power and its cornering and handling ability were stunning considering that the R8 was running mere street tires. The R8 was well balanced and exhibited very little body roll going through the same 23 turns at Miller. The engine sound was one of the best parts – deep and throaty.
If you have a chance to go to an American Le Mans Series race this year, look for Audi’s Vitesse cars. Better yet figure out how to hitch a few laps on board. It was one afternoon we won’t soon forget.
- Photo Gallery: ALMS Vitesse Program
- Motorsports Discussion Forum
- External Link: American Le Mans Series
- External Link: Champion Motorsport