If you're wondering why he'd want to do such a thing, it's to provide the wheel with what's called negative camber. Scott claims this can simultaneously improve performance, handling, ride and fuel efficiency. It involves a trick long used by sports car makers to give their tires more contact with the road during cornering. Manufacturers have generally added negative camber by adjusting the suspension, which improves grip but tends to produce a a bumpy ride and excessive wear and tear on parts of the tire's tread. Scott's idea is to modify the tire itself to achieve the handling and ride benefits of negative camber -- without the downside.
Because the CamberTire strikes the road -- bumps, cracks and all -- at a slight angle, there's less jostling for passengers than would be normal for a sports car with conventional tires. Similar to a boat's bow cutting through the water, said Optima spokesperson Denise Harris, the CamberTire strikes bumps at a slight angle, minimizing the initial impact and transferring it across the tread surface as the tire rolls along.
"You could put your 90-year-old grandmother in a high performance car and she'd be entirely comfortable riding across the country," said Scott, adding that the ride quality could be up to 10 times better with CamberTires than with the stock tires for performance cars.
Scott secured a patent more than a decade ago for a tire with a constantly decreasing diameter, and now he's working with a 7-person team to bring his invention to the masses. It's an ambitious goal, but Scott claims "distributors are clamoring" to get the CamberTire. He aims to secure licensing deals with tire makers and major car companies, while also working to scale up Optima's own manufacturing capacity.
Although the company has yet to complete tests determining how much efficiency might be gained through these designs, Scott claims his design offers a number of environmental benefits. To start, the CamberTire can deliver more performance using less material. With a square tire, Scott explained, you would need a wider tire to get the same level of grip that can be achieved with a narrower tire with negative camber. That means CamberTires require less raw material, weigh less and deliver a lower wind profile, compared to currently available options, he said.
Negative camber can also eliminate the need for what's called "toe-in," an alignment setting that increases rolling resistance and tire wear. Typically wheels are set slightly pigeon-toed -- forcing one tire against the other -- in order to keep the steering feeling centered, Scott explained. But when the tires have negative camber, they "want to turn in."
Ever the inventor, Scott told us he's already looking ahead to new designs. While his initial CamberTire design features just two degrees of camber, he said he has developed a pair of tires that have three and four degrees of camber, as well as "rockers," for two different wheel sizes (255/35-18 and 265/35-18 -- nomenclature that means the tires be 255 millimeters and 265 millimeters in width, be 35 percent as tall from wheel to tread as they are wide, and span 18 inches in diameter). He also aims to develop a 3-inch-wide tire with a whopping 15-20 degrees of negative camber for an "extreme fuel economy car."
So far Scott has personally funded the whole CamberTire project (Harris emphasized that the small team has also put in a significant amount of "sweat equity"), and he's looking to bring in some investment, in the range of $500,000 to $1 million, from friends and family while shopping around for partners, customers and potential acquirers. In 2010, he said the company will produce an estimated 5,000 tires through its partner M&H Racemaster. Next year, he expects to produce "hundreds of thousands" of CamberTires.
Scott's lofty goals don't stop there. Long term, he's hopeful that the U.S. government will require negative camber tires on every car sold in the U.S. due to their capacity to make vehicles more "predictable and controllable," and also more efficient.
For now, the job at hand is winning over customers and partners. Scott said the products are slated to hit the replacement tire market next year, and Harris told us the company hopes to make its first major commercial deliveries within the next 12 months. But when it comes to a timeline for when big automakers might use the design on mass market vehicles, he declined to venture a guess. If it were up to him, he said, "it would be eight years ago."