Danny Thompson has been working to break the record for piston-powered cars during Bonneville Speed Weeks for more than eight years.
Using the Challenger 2 chassis his late father, Mickey, constructed (with the help of Kar Kraft) in 1968, Thompson’s third try with the resurrected twin-engine streamliner was the charm on Sunday, August 12th. His Thompson LSR team achieved a new, two-way AA/FS record of 448.757 mph.
“This has been the goal since day one of the project,” Thompson said. The trials have been many along the way. In 2016, Challenger 2 made its first appearance but was unable to run, as the salt was too wet at Bonneville for any competitors to make their Speed Week attempts.
Last year Thompson turned a 435-mph on his first trip down the five-mile circuit, only to have it all go awry the following morning when a single connecting rod broke on the return, putting a hole in the block and damaging the balance of the bottom end, failing to set the record he’s been aching to hold.
Running two engines front and rear was what Mickey Thompson set out to do, but son Danny found better ways of putting the streamliner together. Modern race engines are far better than they were 50 years ago; overall technology is head and shoulders above what Mickey Thompson had at his disposal in 1968. After the elder Thompson’s 1968 attempt was rained out, following year sponsor Ford pulled out of racing and the racecar began a long siesta.
Challenger 2 was resurrected using a pair of Brad Anderson Hemi-type nitromethane-burning Top Alcohol engines mated to two “Hadley boxes” that allow the two engines to be mounted backwards (front engine) and forward, the rear engine using a reverser for synchronization. With the Hemi-style engines wider than the original Fords, adjustments to the chassis had to be made. All of these changes to the running gear and the chassis/body explain the immense amount of time it took for Thompson and his mostly volunteer group to break the record held, until Sunday the 11th, by George Poteet’s Speed Demon, at 439mph.
For this year’s Speed Week – and the 50th anniversary for Challenger 2 – Thompson and his crew were determined to have success. After setting up shop and doing race prep on Friday, Thompson’s first run, performed mid-morning on Saturday the 10th, was a pass through the long-course traps at 446.605mph, with an exit speed of 453.682mph. Thompson said it was “a pretty hairy ride;” one of the two Brad Anderson engines broke a valve spring, but the team was able to replace parts during four hours’ impound when they were permitted to work on the car.
Determined not to have the problems he’d experienced a year earlier, Thompson and his team were on the Flats by sunrise. The team added a bit more nitro (another three percent) into the mix, bringing it to 87%. That added, Thompson said, about 7-800 horsepower. When he accelerated into third, final gear, “It went sideways on the shift, spun the tires but came back to us. We might have lost some speed but we came back with a result close to 460,” he said.
As Thompson greeted his wife and his mom he exulted: “It’s magical. It’s been eight years to make this day and I’m the happiest man in the world. This is it for Challenger 2. We’re done. I can’t thank the crew enough, and my family.” The result? A second run of 450.909 mph with an exit speed of 459.588, for a two-way record of 448.757 mph.
After this, there’s no reason to come back. The job’s been done; Mickey Thompson’s son fulfilled his father’s dream of racing the fastest piston-powered racecar in the world.
Today’s time slip. 450.909mph. We backed up the record! pic.twitter.com/8njj9EFto5
— Danny Thompson (@thompsonlsr) August 12, 2018