Volume IX, Issue 10, Page 54

News & Analysis


Tire issues in the nitro classes are still a major problem

This is the second part of a three-part series on the problems facing major league drag racing in the post-Wally Parks and pre-HD Partners era.

he major sanctioning bodies in North America, the National Hot Rod Association and the International Hot Rod Association, plus the major sanctioning bodies in Europe and Australia, have all had continuing issues with the Goodyear tires that are used by Top Fuel and Funny Car teams world wide.

In 1993 Kenny Bernstein in Top Fuel and in 1994 Jim Epler in Funny Car broke the 300-mph barrier for the quarter mile and let that genie out of the bottle. Beginning in 1994 when Top Fuel speed regularly began exceeding 315 mph, both of those classes began to experience the phenomenon referred to as “tire chunking.” Amazingly that problem continues to this day, almost 15 years later. I can find no one who remembers any tire failures such as the sport is plagued with now prior to the 300-mph barrier being broken.

Unfortunately for Force, the tire blew, for reasons as yet unknown, at the end of the run, just as he was deploying the parachutes.

— JFR press release after his Motorplex crash

At the same time, the sport started experiencing chassis failures with the bottom frame rail of Top Fuel cars breaking. Jack Ostrander’s chassis failure and crash at Gainesville is a classic example. As best we can tell, the breaking of the 300-mph barrier and the subsequent increases in engine power, down-force application, and track prep technology -- all aimed at delivering increasingly quicker ET’S and faster speeds -- caused a quantum leap in the cost of fuel racing.

The research I’ve done, which includes interviewing prominent tuners, drivers, car owners and a former Goodyear tire engineer, indicates that the sport’s on-going problem with tires can be traced to a couple of issues. According to Les Garbicz, who worked as a tire engineer for Goodyear from 1977 until he left the company on good terms in 2003. He was the main drag racing tire engineer from 1995 until 2003. One of the most pressing issues is that Goodyear is basically working with a tire that was designed about 20 years ago. He cannot reveal specific details of tire design because of a confidentiality agreement regarding trade secrets he agreed to with Goodyear when he left the company, but he was willing to talk about his experiences.

As fuel cars began to regularly exceed 300 mph the racers began to have issues with tires “chunking.” During my conversation with him, Garbicz said during that period he was involved with the inspection of all of the fuel tires that had failures and he was very explicit that he did not feel any Goodyear slick ever had what he called a “hard” failure. He defined that as a failure where the tire came completely apart due to faulty construction. He went on to say that the tires did have what he referred to as “soft” failures, which he categorized as tread separating from the carcass. 

He also stated categorically that every hard failure he and his team investigated could be traced absolutely to some outside issue such as bad maintenance or foreign objects on the track or something coming off the car and penetrating the tire.

“I can tell you that Goodyear did everything a manufacturer could to produce a quality, safe tire. Each tire was X-rayed and inspected many, many times before it got to the track,” he said.

During his time with Goodyear Garbicz says he tried to work with the NHRA and the teams about the tires. He and the Goodyear engineering people had discovered that the problem with their tires was that with the aero down-force created by the wings and the then-current design of the tires combined with the inherent heat generated by a slick spinning on a track, the tires simply couldn’t shed enough of the heat developed internally to keep the rubber that was bonded to the carcass from literally boiling and losing its adhesion.

“The tires have to have controlled spin in order to shed heat,” Garbicz explained. “If they don’t spin, the tire just gets hotter and hotter internally and eventually the (slab) separates from the carcass.”

So Goodyear, the tuners, and the NHRA were faced with a major problem. In order to go faster the tires needed to hook up better, and that meant the NHRA had to do better track prep and the tire engineers at Goodyear needed a tire that would handle the stress and heat. At that time NHRA evidently felt that quicker and faster was what the fans demanded.

In an effort to deliver a safer tire, Goodyear and Garbicz went back to work and designed an improved version of the then-standard 36-inch tall, 16-inch wide tire. They made the tread 17 inches wide and the rubber compound a little harder. Garbicz and the engineers had found that the square edge area of the standard tire retained more heat, so they rounded the corners of the tire to help release more internal heat. That version of the tire shed more heat and had less chunking, but the crew chiefs were having problems launching their cars at that time and they blamed the tires.

“I went back and added another half inch to the width and that seemed to solve some of the crew chief’s and tuner’s problems,” Garbicz said.

Still, though, with the increasing speeds and improving track prep the tires continued to have problems with losing and separating tread.

Garbicz told me that during his time with Goodyear and the NHRA he repeatedly offered suggestions to, among other things, reduce the amount of down-force on the front and rear wings, but basically to no avail. He also said that the NHRA and Goodyear both knew that actually spinning the tires as the car went down track was better for releasing heat from the tire.

“Do you remember Englishtown several years ago when we had to postpone the race? The reason was that the track was so good from the starting line to the finish line that it literally was pulling the tires apart because the tire was hooked-up too good. Luckily for us the race was rained out,” Garbicz said.

I was at that race and can attest to that happening.

So, it seems that the NHRA and the car owners and crew chiefs have known for some time that there was a problem with the tires related to too much heat, too much tire speed, and tracks that are too good. To its credit the NHRA did try to address the situation by mandating a rev-limiter and a reduction in nitro percentage in an attempt to keep the top speeds in the 330 range, but it seems evident that they just didn’t go far enough. The speeds of the Top Fuel and Funny Cars are obviously still too high and the tires are still failing. 

The NHRA wasn’t alone in trying to resolve the tire issue. At the request of Goodyear, Les Garbicz was tasked with designing a new tire that would solve the issues of the tires. According to Garbicz, he went to the drawing board and came up with a new Top Fuel and Funny Car tire. Goodyear knew they had a problem and spent their own time and money trying to fix it since the sanctioning body seemingly chose not to. Garbicz came up with a tire that was 40 inches tall and had 18 inches of tread width.

“I made it 40 inches tall so that the tire speed come down a little, I made the tread width 18 inches wide so that it would throw off more heat.” Garbicz continued, “I think that tire would have solved most of the problems we were experiencing.” 

Goodyear even went to the expense of having tire molds made and producing some prototypes. They took the tire to the SEMA Show.

Garbicz explains his design of the new tire this way, and here I’m paraphrasing what he said. Look at the tires in all classes of cars from Jr Dragster up. As the cars get bigger and faster the tires get bigger. So why do we have the same size tires that we are using on alky dragsters and Funny Cars? Cars which make, say, 3,000 hp using the same tires as cars that make 8,000 hp. That doesn’t make much sense, does it?

Unfortunately for everyone, that tire was rejected. The car owners didn’t want the tire because using it would mean that both the Top Fuel and Funny Cars would need to be back-halved plus the Funny Car bodies made wider.

Additionally, Garbicz says that a couple of prominent crew chiefs were adamant about not bringing in a new tire.

“I had one famous crew chief almost stick his finger through my chest telling me that the tire would never be approved because it would make all of the data he had accumulated over the years using the old tire useless. He was worried about his job security,” Garbicz told me.
Once again, a classic example of the teams making decisions concerning safety and the future of the sport, instead of the sanctioning body and Goodyear.

In the end the new tire was allegedly rejected by a PRO committee and the NHRA -- a tire that might have solved the tire problem we have now and perhaps saved a couple of lives.

There is no hard data to indicate that Les Garbicz’s tire would have solved the problem, but the NHRA management evidently didn’t have the will to tell the racers that they (NHRA) were going to test the tire and would make a decision about its use. The larger question is why Goodyear, who is the only tire manufacturer for the nitro classes, didn’t do what they do with NASCAR and simply tell the NHRA racers that the new tire was what they were going to use.

At the end of my conversation with Les Garbicz I asked him point blank if he thought the speeds the cars are going now contributed to the problem. He said it did. I asked him at what speed he considered the tire that he developed to be safe. After a long pause, his answer was “305.”

No one can prove absolutely (as far as I know now) that a tire failure has caused any deaths in Top Fuel and Funny Car racing. But we do know that they fail and do so regularly. We now know that at least one former Goodyear tire engineer thinks there is just too much speed and too much down-force for the tires to be considered safe.

Going into the next season the NHRA and HDP are facing a PR crisis because of the Medlen and Force crashes. Just as NASCAR, IRL and even the F-1 folks had to deal with cars simply going too fast, so will the NHRA. What will it take for the NHRA, IHRA or Goodyear Tire and Rubber to just say no? What happens if Julie Russell decides not to settle out of court? Right now she certainly doesn’t seem to be in a position of weakness considering recent events. A sympathetic jury might decide to punish Goodyear and the NHRA and award punitive damages in the nine-figure range.

Why the NHRA, Goodyear, and the PRO just don’t get together and fix the problem is a question with no good answer, but certainly one a for-profit public company’s board might ask of the President and CEO.