Rallycross
7 reasons why World Rallycross' RX2 cars are serious pieces of kit
They might lack the bite of their 600bhp Supercar big brothers, but the cars in the World RX's feeder series are still mightily impressive.
Rising rallycross star Cyril Raymond claimed the RX2 International Series title for the second time in 2017.
The French driver plans to graduate from the single-make support category to top-flight FIA World Rallycross Championship action in 2018, to join fellow former RX Lites – the previous name of the rebranded RX2 series – champions Kevin Hansen and Kevin Eriksson in World RX.
Cyril Raymond with his title-winning RX2 machine
© Jaanus Ree/Red Bull Content Pool
But what about the cars that took Raymond, Hansen and Eriksson to their junior titles? Here’s why RX2 machines are serious pieces of kit, and provide a great learning ground for aspiring World RX drivers.
1. They’re four-wheel drive
Just like their bigger Supercar brothers, the RX2 cars (known as Supercar Lites) have four-wheel drive, using a longitudinally-mounted transmission and mechanical differentials.
“The cars are fun to drive,” says Raymond. “You have to turn in very early before the corner because they are four-wheel drive, then in the middle of the corner you begin accelerating with the steering wheel straight.”
“The fact that the RX2 cars are four-wheel drive is a big positive for the series. It makes it clear that it’s where you need to drive if you want to be a World RX driver,” adds Kevin Hansen, who won the class crown in 2015.
Kevin Hansen learnt his craft in an RX2 car
© @World/Red Bull Content Pool
2. They have a six-speed sequential gearbox
Again just like the Supercars, RX2 machines have a six-speed sequential gearbox, courtesy of Sadev. The clutch (a twin-plate Alcon item) is only required for pulling away and stopping; gear changes once the car is moving are done without the clutch, as is the case with most high-performance competition cars.
“Because you don’t have to use the clutch, you can brake with your left foot," says Raymond. "The gearbox has a very nice feel."
Looking back on his time racing a support-class machine, Supercar driver Kevin Hansen says: “It’s a great four-wheel package. It’s reliable, fast and has a good feeling. The function on track is really good.”
Cars run a six-speed sequential gearbox
© RX2
3. Each car has a powerful naturally-aspirated engine
The cars are powered by a 2.4-litre Ford Duratec engine, developed by Mountune. They produce 310 horsepower and 300Nm torque, approximately half that of a rallycross Supercar, but plenty for the support category racers to deal with.
“The engine is powerful and very nice. You can rev it to a very high rpm before changing gear,” says Raymond. “It’s easier to learn with when you’re starting in rallycross, and they sound very nice.”
While the World RX Supercar engines are 2.0-litre and turbocharged, Hansen agrees with Raymond that the naturally-aspirated RX2 motors provide good training in the mixed-surface discipline. “It’s great that it’s a non-turbo engine," he says. "You have to have a perfect understanding of how the power is delivered. The throttle position is very linear to the power you get out of it."
The cars pack as much as power as a 2016-spec World Rally Car
© RX2
4. The engine is mid-mounted
Mid-mounted engines are generally associated with high-performance vehicles, and it’s no different in this instance. An RX2 car’s engine is located behind the drivers’ cabin.
“The mid-engine makes it a very unique feeling to drive the RX2,” says Hansen. “I always [used] that weight distribution to make the car oversteer, [but] then it’s hard to stop that smoothly because the weight at the rear is moving. You have to be very smooth in your driving all the time.”
“I think it’s a good idea to put the engine there," adds Raymond. "The car is stable for me and we don’t have bad effects from the weight."
5. They have inboard suspension
Akin to many circuit racing cars, the RX2 racers have inboard suspension, in contrast to most rallycross cars which conventionally use a McPherson strut or double wishbone design. The RX2 machines also use double wishbones, but with their Öhlins dampers lying horizontally in the chassis, connected via a push-rod.
“This makes the car stable and means you don’t have too much movement in the chassis,” says Hansen. “There isn’t a massive range of setup changes you can make, but it’s a perfect amount. For example, a private or family team can enter with a car and make it fast, like we also did with factory support. You have to balance the car on its absolute limit, because if you start to slide on tarmac you don’t have enough power to make it efficient. On gravel it’s the opposite. There you need to be on maximum attack because you don’t have enough power to keep it on the front wheels.”
Many rallycross circuits, especially in Scandinavia, have at least one jump. Due to having more limited suspension travel than the Supercars, it’s important for drivers to take off and land in the correct way in RX2. “You have to be very straight when you start your jump, or sometimes the [landing] is not very comfortable,” notes Raymond.
Check out the horizontal Öhlins dampers
© RX2
6. They have lightweight bodywork and tubular spaceframe chassis
The tubular spaceframe chassis, with detachable frames front and rear to allow for quick changing and easy access, are clad with lightweight composite bodywork which can also be removed or replaced far more quickly than with a steel bodied car. The total weight of the vehicles is 1,100kg, including driver.
The spaceframe chassis keeps weight down to 1100kg
© RX2
7. All the chassis are identical
With adjustments limited largely to the suspension settings, the RX2 drivers compete in identical machinery, allowing talent behind the wheel to shine.
“It’s hard to make the difference on track," explains Raymond. "You have to be perfect with your lines. If not then you lose a tenth [of a second] straight away because everyone has exactly the same car."
“One-make cars with a very narrow range of setup options makes it a series for drivers to shine and not engineers. I think the car is amazing as the second category of World RX,” concludes Hansen.
Watch Cyril Raymond winning the final of the Lydden Hill round of the 2017 RX2 series in the video below…
RX2 car specs:
- Engine: Naturally-aspirated 2.4-litre four-cylinder Duratec
- Power: 310bhp
- Torque: 300Nm
- Gearbox: Sadev six-speed sequential
- Clutch: Alcon twin-plate
- Suspension: Double wishbone front and rear with Öhlins TTX adjustable dampers
- Brakes: Alcon 330mm ventilated brake discs with four-piston callipers front and rear
- Wheels: 8” x 17” lightweight KMC rims