A hard tire does not adhere well to a rough surface because the contact patch does not con
Is Soaking That Effective?
There are various claims made by those who use and sell tire treatments about how effective the treatments are. The real numbers depend a lot on the driver's experience level, the setup in the car, and the racetrack itself. Claims of lap times two- to five-tenths lower may be valid for a worn-out track, whereas you might not need to soak the tires at all on a newly paved track. True average lap time gains are in the two- to three-tenth range. That could be the difference between starting and running in the Top 5 or the middle of the pack.
Many companies claim the tires will run cooler and last up to 50 percent longer by using tire treatment. The lower temperatures, they say, are due to the fact that a tire that grips the track better will slide around less, causing less heat and generating friction. More grip also reduces the amount of wear because the tire is not scuffing off little pieces lap after lap.
Tire treatments generally do not make the tire sticky. Chemicals that would do that would also cause the tire to wear excessively and not last but a few laps. The modern blends will make the tire surface more flexible so that the face of the tire can conform to the track surface. The rougher the track surface, the more difference the treated tires will make. It's all about helping the tire make complete contact with the entire surface of the track instead of sitting atop the peaks and missing the valleys like a hard tire will do.
Used tires can be brought up to near-new grip capability simply by applying treatments to them. This allows a team to run the same tire for several weeks if the races aren't too long. For a track that runs feature races of 35-50 laps, a team might expect to use a set of tires for several weeks before needing to buy new tires and still be competitive.
Many teams on the low end of the budget scale will buy low-lap-count used tires from the teams who can afford new tires every week. They treat them, and then, with the right setup, are able to compete on a fairly even basis with the high-dollar programs.
Is This Good or Bad for the Sport? Depending on your conversation, racers who use tire-enhancing compounds are either ruining the sport or causing it to grow. Most racetracks forbid the use of tire treatments. Some are aggressive in enforcing the rules while others tend to look the other way, or worse, practice selective enforcement for whatever reason.
An indentation-hardness durometer reading can be inaccurate. We read a used tire in three
Irwindale Speedway in California went so far as to bring in a tire "dope"-sniffing dog that had been trained to sniff select chemicals that are used in most tire treatments. It worked; the first night, several hits were recorded and those teams were told to not come back with treated tires. (See sidebar)
Many tracks rely on tire durometers that are used to measure the indentation hardness of the tire. The use of these instruments is subjective and inaccurate at times. The tire must have been run and heated in order for most of the soaks to work. Therefore, on a cold tire, or one that has been allowed to cool sufficiently, the reading will be fairly normal.
The durometer reading itself is indicative of the age of a new tire. For a new batch of tires that may have just arrived from the tire manufacturer, the reading might just be near the softness limit, while a few months later with the vendor selling from the same batch, the reading might be much higher. Suppose I purchase a set from a newly "hatched" batch, wrap them in cellophane, and store them in a cool, dark place. When I go to use them later on, they will read a lot softer than other tires from the same batch that have hardened after being stored in a trailer, enduring high heat day in and day out. The difference can be substantial and I have not cheated by soaking the tires, but I may well be a target of suspicion and disqualified nonetheless.