Travis Pastrana didn't have an easy job setting a new course record in his specially prepped WRX STI.

Earlier this year, Travis Pastrana set a new course record up the 7.4-mile (11.9-kilometer) Mount Washington Hillclimb, and now Subaru has celebrated the big accomplishment by releasing a documentary highlighting the work that went into the attempt.

Subaru showed up to the Mount Washington Hillclimb intending to set a record. Rather than its standard rally setup, the team brought a pair of specially prepared the STIs with the 600-horsepower (447-kilowatt) engine out of a Global Rallycross Championship racer. The cars were also lighter than usual and had a tarmac-tuned suspension.

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The extra power made the STI quite a handful. According to Pastrana, corners that he usually took with the throttle wide open now required him to dab the brakes. The changed forced him to completely re-learn the course because known of his previous knowledge applied. Making the run even more difficult, he didn't have a co-driver calling pace notes, so Pastrana had to memorize the whole route.

Pastrana's run came with the extra stress of knowing that setting the record was up to him. Just before setting off, his teammate, David Higgins, went off the course near the top of the mountain. He didn't suffer any injuries, but his STI wasn't able to make another attempt. 

The pressure didn't get to Pastrana, though. His time of 5:44.72 crushed the previous record of 6:09.09, which Higgins set in 2014.

Subaru has had quite a summer for setting records. In addition to the run at the Mount Washington Hillclimb, the company also sent a specially prepped STI around the Nürburgring and set the fastest time ever for a sedan around the famous course.

Source: Subaru via YouTube

Subaru Mount Washington Record Documentary