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Motor Sports

INDY CAR TIRE WARS

by Tony Sakkis

January 31, 1997

Over the past two seasons, Indy Car -- meaning the IRL and CART Indy Car -- have been in locked in an honest-to-goodness tire war, with Firestone clearly taking an edge as Jimmy Vasser won the championship on a Firestone-shod car, and co-champions Scott Sharp and Buzz Calkins won the IRL title with the same manufacturer.

But we must not forget that tires have probably contributed to the overall safety and performance of the sport far more than any other single component in the last two decades.

Early racing tires on Indy Cars used fabric carcasses on clincher rims. The fabric developed a great deal of heat as they rolled, usually doubling the pressure from 50 to 100 lbs in just a few laps. They were not very safe, to say the least.

The balloon tire from Firestone -- dubbed the Speedway Special -- was the first purpose-built racing tire. Firestone pretty much monopolized the sport for the next several decades, and didn't do much development except to perfect the balloon design.

In 1963 Firestone developed a smaller tire to go on a fifteen inch Halibrand wheel. The drop from 18 inches to 15 caused some alarm that the footprint wouldn't be big enough. So Firestone increased the width another inch-and-a-half. Lap speeds immediately jumped and teams scrambled for both wheels and tires.

That seemed a good enough time as any to enter the fray, and the Goodyear Tire and Rubber began testing its own racing tires, ultimately creating the contemporary prototype for the race tire wars. As Ex-Director of Racing at Goodyear Tire and now IRL official, Leo Mehl explained that it was a decision prompted by a need that wasn't being addressed by Firestone.

"Firestone was running those little skinny tires and Lotus came with Dunlops on the rear engined cars," the amiable Mehl said, "and Foyt asked for Dunlops on his roadsters. They told him they weren't for roadsters; that they wouldn't last. Foyt said, 'Hey, it's my butt, let me try them'. But they wouldn't do it. That's when he got on a plane and went to Akron, Ohio and knocked on the door of the Chairman Of The Board and asked if we could help him. It took us five years to finally beat them."

Tire widths almost doubled in a few short seasons, the profiles dropped creating fantastic lateral stiffness, tread compound improved ... and lap speeds jumped ten miles per hour. By the end of the sixties, the typical Indy Car tire was twelve inches across and had was a 40-series profile (the profile was forty percent as wide from the bead to the top of the tire's outermost diameter as it was tall -- when ten years earlier they had been taller than they were wide) and far stickier. The war had begun and Goodyear was winning it.

Firestone left Indy Car racing in 1975 and Goodyear has been on its own ever since. In the recent past, Goodyear was the show. There was no competition, and they were able to develop the speedway radial, among other safety-oriented products. Without competition, Goodyear focussed on other areas.

In 1994, Firestone returned to Indy racing. There was a tremendous amount of development right away, with an emphasis on winning -- just as it was in the mid-sixties.

So far, the fans have won, seeing better races and more varied competition; the series have won, with more battles going on within the races; and the drivers have been at the mercy of the manufacturers and the conditions of the various racetracks.

So far, everything is working out well. But one must wonder about the limits of adhesion and how fast is too fast. The tire war is healthy so far. Hopefully that will be the extent of it.