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M. Bonner Denton is highly regarded for his work in analytical chemistry, but recently he has been recognized for driving himself into sports car racing history.

M. Bonner Denton is a University of Arizona professor highly regarded for his work in analytical chemistry. He's currently developing devices that can detect hidden explosives with a thousand times more sensitivity than anything now available, but that's another story.

Denton is also known for breaking land speed records at the legendary Bonneville Salt Flats Speedway, where he's just driven himself into sports car racing history. Denton was officially clocked at speeds greater than 300 mph on the Bonneville Salt Flats on Aug. 20.

"We were already the world's fastest sports car, but when we qualified at least on one pass at more than 300 mph, people went crazy. That's never happened before," Denton said.

Denton posted an initial qualifying run of 268.772 mph on Aug. 18, with a second qualifying run of 292.241 mph on Aug. 19, and raced the course at 305.726 mph on Aug. 20. At the last speed check in the final pass, he was clocked at 310.398 mph.

"I saw the 5-mile marker go by and thought, 'That shouldn't have gone by yet. I don't want to stop if that wasn’t really the 5-mile marker.' But I decided it really was the 5, and popped my parachute. My accelerometer showed over 2 G's deceleration."

Denton's official average speed for the last two of his runs averaged 298.983 mph, or more than 44 mph faster than the previous record set in 2002. The 6-year-old speed record that Denton demolished was his own.

He set the 2002 record of 254.138 mph with the same car, named "Bonner's Bad Berkeley," that he began racing on the 47-square-mile Salt Flats in northwestern Utah in 2000. Bonneville Nationals, Inc., and the Southern California Timing Association have been the governing bodies and official timekeepers for speed racing aficionados since 1948. Bonneville is the last domain for amateur drivers to compete on a world-class level, Denton notes.

Denton's car is a highly modified 1959 Berkeley. The car body is classic, vintage British-made Berkeley behind the dash, but Denton built the aerodynamic custom car from the dash forward in Tucson.

"That's where science and technology comes in. You have to be knowledgeable about aerodynamic forces," Denton said. "What you want to do is build a car that will not fly. We hope not to fly, but quite frankly, I never intended this car to go much over 300 mph."

Racing sports cars do go airborne and flip at high speed, and it has been fatal.

AA sports car class rules allowed Denton to stretch the front of his car to the maximum of its 130-inch wheel base. The entire car is 180 inches long.

The "AA" class is for cars with greater than 500 cubic inch engine displacement. The 540 cubic inch Chevy engine in Bonner's Bad Berkeley runs on $12-a-gallon gasoline, consumed at a rate of 4-to-5 gallons during the 90 seconds it takes Denton to cover the 5-mile course.

Garrett AiResearch provided the engine's twin turbochargers capable of withstanding 1,800 degrees Fahrenheit. Denton loads the car with 100 pounds of ice before every run to feed an ice water system that cools hot air from the turbochargers before the air is blown into the engine, which runs somewhere around 2,400 or 2,500 horsepower.

Sports car class rules permit 2-wheel drive only, so Denton opted for front-wheel drive for weight stability reasons. Front-wheel drive, plus a front body that clears the ground by less than an inch, helps prevent the machine from going airborne.

"We're limited to a 130-inch wheelbase, so you want front-wheel drive as you want to pull, not push, your car through the salt," Denton said.

The Salt Flats are nothing like pavement. They are the consistency of wet sand, and so it's like driving through one to two inches of wet snow. "You slide all around, and you see a big rooster tail of salt coming off the back of the car at that speed," Denton said.

Bonneville Speedweek is always in August because that's when the salt is best for racing. Each year, Southern California Timing Association members scout out the best salt to race on, and drag out 3-mile and 5-mile courses. Club members mark course lanes by painting black lines on the salt and setting orange markers at every half mile.

The marked course is easy to lose, especially if you're racing east at almost 300 mph, blinded by early morning sun in your eyes, Denton said. He was blinded and veered slightly outside the 5-mile timing light at 7 a.m. Aug. 19, so that run didn't count. "I don't know how fast I was going – but it was fast," he said. That afternoon he qualified at 292.241 mph, with an exit speed of 301.183 mph.

Early Aug. 20, the day of his official fastest run, "I put electrical tape across the top of my helmet visor so I could position my head up and down to block out the sun and see where I was going. And we ran 305.726 mph, with an exit speed of 310.398 mph. We could have gone faster, but we went against the 'rev limiter,' a safety feature which kept the motor from going faster. We had the rev limiter set at 7,200 revolutions per minute, but we can safely run up to about 8,000. We have a lot more motor to go."

Denton plans to do that next August.

"The beauty of Bonneville is that it's one time a year. You have a whole year to get ready for the next race, so you can work around a full-time university career," he said.

The Texas native began building and racing cars in high school. The first car he built was a 1929 Model A Ford with a Chrysler hemi with eight carburetors. The car was not just unreliable, a friend quipped, "but unsafe on jack stands."