European Rallycross’s back-to-back champion Timur Timerzyanov talks us through his Citroen Supercar.
550bhp, 0-100kmh in 2.5 seconds and built for ‘Mad Max’ style racing: rallycross’s Supercars are among motorsport’s most outrageous machines and here’s an ‘under-the-skin’ look at the crème de la crème from 2013 – Timur Timerzyanov's Citroen DS3 prepared by Hansen Motorsports.
Two ‘gear levers’?
Timur Timerzyanov: “Ah, the first is the normal one – six gears plus reverse. The second is actually the handbrake. We don’t have a central differential so it means we have a handbrake with a clutch on the propshaft so it’s a little special.”
“I don’t touch the handbrake at the start. Instead we have a special, electrical all-in-one ‘lock system’ button on the steering wheel – this locks the brakes and means I can be in first gear and with my foot on the throttle at about 7800rpm. The car will only go when I hit the button in reaction to the lights. The handbrake is for low-grip corners, to change the car’s direction. It’s like a pointing stick!”
“All the engine sensors give signals to the ECU and what you want to pick is on the dashboard. I can see my lap times, RPM and some warning lights, plus I can change the engine mapping.”
“It glows red hot at the starts as the catalytic converter heats up. Then you get exhaust flames when we’re off the throttle…this is excess fuel burning off. We use excess fuel to cool down the engine or to negate anti-lag, so the boost level stays high.”
“It’s not so far above normal road-spec fuel, 102 octane. We burn about six litres per 10km. The fuel tanks are only about 20 litres capacity, to keep the weight down and also for safety.”
Brakes & suspension
“The discs are only 310mm to save weight but the stopping power is immense. The suspension is the big area…with the braking, traction and side forces it’s a lot into the suspension and you really want the wheels to stay fully in contact with the track. A basic damper for one corner costs €4000 but then there’s development. There are millions of configurations and you never stop learning.”
Wheels & Tyres
“We run Speedline wheels. They are designed to take the forces and stresses from the track but also to flex. The Cooper tyres we use are 17 inches and very special – they are all hand-built.”
“This obviously is for safety but they are complex designs and also help a lot the car’s performance. The tubing deliberately goes to the suspension points. You want the chassis to be as rigid as possible but there’s always going to be some flexing.”
“The wings and passenger door are carbon kevlar but can be no thicker than 2mm. They are designed to absorb side impacts, but also so they can be replaced quickly by the mechanics. The driver’s door has to be absolutely standard for safety so it’s quite heavy.”
“Our engine is based on a two-litre diesel block from Citroen which, on the road, produces maybe 160bhp. Our engine builder ORECA turns that into nearly 600bhp! There’s a special crankshaft, for example. The air restrictor is 45mm maximum and you need a good ECU to inject the fuel correctly. The engine is rebuilt after every second event.”