How come F-1 uses rain tires and Nascar doesn't?

Question

Is it because the F-1 cars are lighter than the Nascar cars. I have watched a few Formula One races, and whenever it rains you just put on rain tires and just keep racing.

Answer 1

Rain tyres have a specially designed structure making them better adapted for their application than any other tyres. However not all rain tyres obey the same design priciples. Certain factors need to be taken into account when designing a good rain tyre, such as the:

-speed of the car
-weight of the car
-power of the car
-lifespan of the tyre

Rain tyres are cut or moulded with patterned grooves or tread in them. This allows the tyre to quickly displace the water between the ground and the rubber on the tyre. If this water is not displaced, the car will experience an effect known as Hydroplaning as the rubber will not be in contact with the ground.

These grooves do NOT help the car grip contrary to popular belief, however if these grooves are too shallow, the grip will be impaired in wet conditions as the rubber will not be able to make good contact with the ground. The patterns are designed to displace water as quickly as possible to the edges of the tyre or into specially cut channels in the centre of the tyre.

Not all groove patterns are the same. Optimal patterns depend on the car and the conditions. The grooves are also designed to generate heat when lateral forces are applied to the tyre.

Rain tyres are also made from softer rubber compounds to help the car grip in the slippery conditions and to build up heat in the tyre. These tyres are so soft that running them on a dry track would cause them to deteriorate within minutes. Softer rubber means that the rubber contains more oils and other chemicals which cause a racing tyre to get sticky when its hot. The softer a tyre, the stickier its gets, and vice versa with hard tyres.

Sometimes rain tyres are designed to have a smaller diameter than their dry counterparts. This means that the wheel spins faster and more water is thrown off the tyre by centrifugal force. Some rain tyres are also narrower than the dry counterparts. This smaller "footprint" reduces the chances of hydroplaning.

Answer 2

Interestingly, weight and narrow tires tend to mean more grip in situations where traction is limited... yes, there is less surface area, but there is more pressure on a smaller area, forcing the tire to the pavement.

So weight and tire width are not the issue. And windshield wipers and lights? Sports cars have managed to race in rain for many years... it's not THAT difficult of an issue to set these up on the cars (actually, more of an issue for open cockpit cars - no wipers for the helmet visor or headlights in F1). So that isn't it either.

Are ovals just too much of a danger? Well, no more so than in the dry... less traction yes, but there would also be lower speeds! And the fact that Busch series races do have the option to use a rain tire makes this seem an unlikely reason.

The only reason I've ever heard stated by NASCAR is that they consider the Cup races to be such an all out shoot out, that they do not want to hold them unless the teams can go all out.

Oh, and as has been pointed out, Bridgestone is the tire supplier in Formula 1.

Answer 3

Back in the day NASCAR was going to and planed on using rain tires on there road course tracks that they went to starting at the Japan track that they finished there season up at for 2 years. The only thing was it never rained so instead of keeping the rain tires at the road course track races they scraped the idea. They even had wind shield wipers too.
The ovals is just not a good idea to run on when they are wet. Doesn't matter if you have the best tires in the world just does not work.
There are class's that are similar to a cup or busch car that do race on rain tires but those class's are ran by descent people and understand what a local yellow is and when too bring a full course yellow out. I don't know if you have watch NASCAR lately but they just love to throw a cautions every chance they get, and a race in the rain would be run under yellow in NASCAR.

Answer 4

Its mainly because of the lack of road courses NASCAR runs.

However, NASCAR did have plans in place years back in which if rain occured during a road course event (and actually implemented at an exhibition race in Suzuka in 1998), rain tires would be used. But when the threat of rainstoms never materalizing (or in the case of Sonoma/Infineon, the race being ran during California's dry season), or only occuring every once in a blue moon during testing, NASCAR eventually ditched the plans to run road course races in the rain. Im sure though if the issue comes up again in the future with rain at road courses, or NASCAR expands to more road courses, the plans will more than likely be re-implmented

Answer 5

Weight has very little to do with it as an F1 car at full speed will have aerodynamic influences acting upon it which effectively increases the cars weight quite significantly.
A slick tyre when used on a wet track will simply not provide enough grip as the tyre will not be able to make sufficient contact with the track surface because of the water on it. That plus the compound of a slick tyre is designed to run at a high temperature so when the rain starts the tyres cool quickly and grip begins to decrease so the drivers can't push hard enough to maintain tyre temperature and thus grip is reduced further.
The wet tyre is designed to lift water from the track to help they tyre gain better purchase on the tracks surface. It is also designed to provide grip an much lower temperatures.
To give you an example of how much work a wet trye does.
Apparently an F1 extreme wet tyre will disperse 35 litres of water from the track per second at 300km/h and the intermediate tyre will disperse water at 15 litres per second.
I'm not sure why NASCAR doesn't drive in the rain as the tyre technology is clearly capable of allowing it.

Answer 6

"Apparently an F1 extreme wet tyre will disperse 35 litres of water from the track per second at 300km/h and the intermediate tyre will disperse water at 15 litres per second.
I'm not sure why NASCAR doesn't drive in the rain as the tyre technology is clearly capable of allowing it."


Rain tires disperse water to the air on an open wheel car. They disperse it back onto the tire and track on a stock car. It's the fender wells........

Answer 7

Not only do they have rain tires, the tires they use are twice as wide as NASCAR's tires which gives them alot more grip and control and they are much less weight which helps. Not to mention that the fans dont want to sit and watch in the rain. I like it the way it is.

Answer 8

They use tires made for racing in the rain when it rains. Nascar does not have any races when it rains because the water might mess up their redneck cars.

Answer 9

F1 cars are open cockpit, while stock cars are not; therefore, in order to race in the rain, they would have to install windshield wipers, headlights, and windshield defrosters. Also, the speeds are much higher on ovals (where stock cars race) than on road courses (where F1 races), which would create visibility problems relating to water spray from the cars in front. The main reason is that it is ridiculously unsafe to race on a wet oval track and that it would be a wreck fest.

BTW, darth whoever the heck you are... F1 uses Bridgestone, not Firestone. The IndyCar Series uses Firestone.

Answer 10

Nascar does use rain tires. Goodyear had them available in Canada when the Busch series raced.

Here are the tires used in Michigan:
Tire Codes: Left-side -- D-4078; Right-side -- D-4062

Tire Circumference: Left-side -- 87.4 in.; Right-side -- 88.7 in.

Technical Inspection Inflation:
Left Front -- 30 psi; Left Rear -- 30 psi;
Right Front -- 48 psi; Right Rear -- 45 psi

Minimum Recommended Inflation:
Left Front -- 22 psi; Left Rear -- 20 psi;
Right Front -- 45 psi; Right Rear -- 42 psi

Here is what was used at the Glenn:

Tire Code: D-4010

Tire Circumference: 88.6 in.

Technical Inspection Inflation:
Left Front -- 23 psi; Left Rear -- 20 psi;
Right Front -- 23 psi; Right Rear -- 20 psi

Minimum Recommended Inflation:
Left Front -- 22 psi; Left Rear -- 17 psi;
Right Front -- 20 psi; Right Rear -- 17 psi

---

Do you see any difference between left side and right side tires on an Oval vs Road Course? There is more traction available to a driver when you are going left and right, than left only. If F1 drivers chose to drive on a oval, they would not be using rain tires either.