PHOTO: Mike Bruno races a dirt-style Modified and an ACT-style Late Model. Guess which tire belongs to which car. (Justin St. Louis/VMM photo)

–by T.J. Ingerson
VMM Correspondent

I’m starting this off on a sad note. Or on a mad note. Either way, I’m displeased with the news that the NASCAR Nationwide Series and Truck Series are not returning to Lucas Oil Raceway (Indianapolis Raceway Park) in 2012.

I get that NASCAR is in the business to make money. But, racing at Lucas Oil Raceway was one of the bright spots for the season, for both series. It took both series back to their heydays, when short tracks ruled the series. I remember growing up watching both these series at the short tracks: Hickory, South Boston, Myrtle Beach, IRP, Nashville, Portland, Mesa Marin, Tucson, Louisville, Portland, Evergreen. The list could go on and on.

Yet, none of those tracks are on the schedule, and some of them don’t even exist anymore. It’s a shame NASCAR has turned their backs on what made their sport.

NASCAR is going from one of their most popular stops on the Nationwide Series, the .686-mile Lucas Oil Raceway, and bringing them to possibly one of the most boring stops, the 2.5-mile Indianapolis Motor Speedway.

Don’t get me wrong. I love Indy. It’s historic. The races are legendary and are full of hype and excitement. The Indianapolis 500, the Brickyard 400, the United States Grand Prix. I get that Grand-Am should be there, too.

But, putting the second tiered Nationwide Series there, running potentially only 40 laps less than Sprint Cup cars? Seriously? Way to be a buzz kill.

Indy has never produced excellent racing for the Sprint Cup cars. The design of the track makes it impossible for side by side racing, thus making it hard to pass. But, for the Sprint Cup Series, it’s the top NASCAR stock car series at a legendary track, and that’s what makes the event. It’s much like the Monaco Grand Prix. The top series racing in one of the most prestigious races in the world. Unfortunately, in my eyes, the same can’t be said for the Nationwide Series race.

Yes, people will point out the Firestone Indy Lights series runs at Indianapolis Motor Speedway. Yes, there are support races for the Monaco Grand Prix. But, how many IndyCar drivers or Formula 1 drivers race in the support races? None. Now, NASCAR will bring the ‘Cup Lites’ in, and in my eyes, could potentially destroy the prestige of winning at the Brickyard.

The only thing that may save it is Jim Nabors. Wonder if he’s available at the end of July.


Wait, all tires aren’t the same? Bias ply, radial; what the heck is that? There are hard tires and soft tires? Now you’re telling me they have different sizes! Different treads, too? Stagger, right, that’s something those people do off Bud Hill.

All that lingo above is actually very important to race cars and their setups. In fact, the driver, crew chief, and team that can better understand the tires over their competition have an advantage. It’s why race teams fight over tires in the tire compounds every week, trying to find that perfect tire or set of tires.

One of the most important aspects of tires, including tires for racing and on your street vehicle, is the construction of the tire. There are two different constructions for tires: bias-ply and radial. If you have watched recent NASCAR K&N Pro Series East champions Joey Logano and Ryan Truex make the move to the NASCAR national series (Sprint Cup, Nationwide, and Trucks), you may have heard the commentators mention the change in tires from bias-ply to radial tires.

Bias-ply tires are seen at almost every race track. The American-Canadian Tour’s 8” Goodyear Eagle G24, the 7” Goodyear Eagle G19 (Sportsman tire), Goodyear’s dirt tires for Sprint Cars, Modifieds, and Late Models, Goodyear’s 10” slick tire for the NASCAR K&N Pro Series, Hoosier’s asphalt tires for Super Late Models and Modifieds, and Hoosier’s dirt tires for Sprint Cars, Modifieds, and Late Models are all bias-ply tires. The cords of the tires run at a 60-degree +/- angle from the bead of the tire, thus running at an angle over the width of the tire. The cords run in both directions, overlapping each other and producing a rubbing effect, increasing rolling friction.

The radial tires, as seen on the NASCAR national series, are slightly different. The cords of a radial tire run at a 90-degree angle, or perpendicular, to the bead of the tire. The cords never cross each other in a radial tire, thus no rubbing of the cords, lowering rolling friction. Many passenger car tires are made like this in an effort to improve gas mileage.

The construction of a bias-ply tire doesn’t allow the contact patch to equally spread out while under load. On a radial tire though, the contact patch equally spreads out, allowing the entire tread of the tire to be in contact with the ground while under load. The result is that a bias-ply’s contact patch is much smaller than that of a radial tire. But, a bias-ply tire is much cheaper, and the benefits of a radial tire are not a huge benefit to short track racing, as short track cars don’t go through the high stresses for extended periods of time as those do on NASCAR national tracks.

One important aspect to tires, especially for dirt racers, is tire compound. For asphalt racers, many tire compounds are determined by the sanctioning body. To be basic, tires can come in soft, medium, and hard. Soft tires are extremely grippy to the race track, but also wear at an extreme rate. It’s short term gain for a possible long term loss. Medium tires are not as grippy as soft tires, but don’t wear as quickly as soft tires either. Hard tires are the least grippy tire to the race track, but they also last the longest.

Dirt track racers that can switch tire compounds can use all three compounds on a given night. On a wet, greasy track, many teams use the soft tire. As the moisture starts to disappear and produces a dry, slick track, many teams will use the medium tire. And, when there is dust in the air, teams will use the hard tire. When there is a lot of water on the track, the track is very slick and the tires must compensate for this with extra grip. But, when the track is dry, it isn’t as slick and the tires don’t need to compensate for this.

Racing tires are all different, from the 12” Hoosier treaded tire used on the right rear of a dirt-style Modified to the 8” Goodyear Eagle slick tire used on an ACT Late Model. Dirt tires are treaded to improve grip. Using a slick tire on dirt has the same effect as using an extremely worn tire during a rain storm: Absolutely no grip.

But why are the tires that the asphalt Sportsman divisions run treaded, too? They use a treaded tire on asphalt to decrease grip, allowing the cars not to corner as quickly.

There is one thing all racing tires have in common: They are specially made for your racing application.

Tires of the same make are also different. If I took two right side 8” ACT Late Model tires and measured the circumference at the same air pressure, chances are they won’t be the same measurement. The difference between the same tires could be as large as an inch, if not more. For measuring them, I prefer using a tire tape measure instead of a “stagger stick.” A stagger stick is a calculated measurement (Circumference = pi (3.14) multiplied by diameter), and therefore I believe isn’t always 100% accurate.

Late Models and Super Late Models use different tires on the left side and right sides. They may consist of different compounds, but usually the right sides are built with a greater circumference than the left sides. This is called stagger.

For almost every race team, stagger is defined as the difference in size between the left rear tire and the right rear tire. Generally, it’s read in terms of a positive number, or how much larger the right rear tire is in comparison to the left rear tire. If you take two tires of different sizes and roll them exactly one revolution, the larger tire will travel the further distance. The same theory applies for a race car. If the larger tires are on the right side, the left sides go a shorter distance, making the car naturally turn left.

Picture a Dixie cup: If you place it on its side and roll it, it turns toward the smaller end of the cup. Tire stagger is the same idea.

For asphalt racing, teams could run anywhere from zero stagger (even sized tires on the left rear and right rear) up to over two inches of stagger. Stagger helps a car turn on an oval track.

For dirt racers, stagger is always adjusting as the track changes. On a wet, slick track, to help the car turn the stagger may be as much as your tires will allow. On a dry track, the stagger will possibly be under an inch.

I hope this helps your understanding of tires. Email me at with any of your questions about anything to do with your race car to help get you in the winner’s circle! Fans are encouraged to email me as well if you want a better understanding of how something works on a race car.