X Games ride-along with Subaru's Travis Pastrana

A slow left-hand hairpin catches Travis off-guard and the left-rear quarter panel of the STI makes contact with a barrier, momentarily halting us. That corner jammed-up Travis before. "That's the second time I hit that," he said, laughing. "We're all human," I replied.

The X Games STI race car

The X Games 2009 Subaru Impreza WRX STI is fundamentally the same as their Rally America race car, but with a larger inlet restrictor, 40mm vs 34mm.

The engine is 2.2L production block boxer 4 with a single turbo -- Subaru wouldn't disclose the boost pressure. The engine makes over 350 hp and an astounding 500+ lb-ft of torque. 

Since the X Games rally car event is a sprint race, a lower life engine is used compared to Rally America spec. The candle that burns twice as bright burns twice as fast.

There's no sound limit in the X Games, but Rally America requires a maximum of 95dB. And while the X Games spec STI has neither muffler or catalytic converter, both are required for Rally America.

Vehicle mass in both specs is about 2900 lb, although Rally America has a minimum weight limit of 2700 lb. Also, the X Games trim removes all the rock shielding panels on the undercarriage of the vehicle to reduce mass, retaining only the oil sump guard.
 
The 2-disc ceramic clutch is mated to a H-pattern gearbox with dog engagement clutches. The X Games STI transmission is non-sequential, but the Ford Fiestas are using sequential boxes which are allowed here.

Travis will have six different tires choices for the weekend: 2 different compounds, 2 different mandated groove patterns and 2 different tread shavings. 140 tires will be used for the three Subaru rally team cars for the race weekend including testing and practice. And all the tires used by X Games competitors are gravel grooved tires, not slicks.

I asked the Subaru tech guy why they use gravel tires -- most of the course is on tarmac. Gravel tires are required in the X Games. Although the stadium section is dirt where those tires are appropriate, the gravel tires slide nicely on tarmac, creating a better show. Marketing genius.

Travis' driving style and The Jump

Travis has a 3-pedal car, but left foot brakes and uses the hand-brake to bring the rear around. He only uses the clutch pedal on upshifts and not on downshifts.

What about The Jump? -- that which separates the X Games from other rally events. Although it looks easy to clear, Andrew Comrie-Picard (ACP) demonstrated last year that is not the case, when he shorted the jump and crashed inverted.

Travis said he just looks at the jump and tries to judge the gap in order to clear it. Some of the other drivers he said look at the speedo and try to get the takeoff speed exactly right. He said that if you do that, the difference between braking and accelerating at the top of the ramp, even if at the same speed, could result in a difference of 10 feet on the landing. Which he might need...

And Travis should know. He's successfully jumped motorcyles without any gauges hundreds of times.

You can watch Travis and his Subaru Rally teammates this Sunday during the X Games Rally Car Racing Super Special Final at 1:30 pm PDT.

Ken Block in action during X Games practice.

Albert Austria, Senior Vehicle Evaluation Engineer, Edmunds, Inc