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Discussion Starter #1
Ok its commonly accepted that wider tires give you better traction and handling, and it seems there are lots track tests that prove it, but I am wondering what this webpage it talking about. It claims that wider tires are not nessicarily better from a traction and even contact patch perception.

http://www.carbibles.com/tyre_bible.html (scroll down a ways)

So I am curious what does everyone think about this? The page seems to make valid points but you look at all the cases where people have put wider tires on and gotten better track times. At the same time the rubber compound and its friction coefficiancy changes between every tire.

Oh and btw regardless, I still support wide rear tires.....
 

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The way I see it...The more rubber on the road, the better. Of course,the wider the tire, the less weight/square inch of contact. When it's wet out, there is not as much weight to squeeze out the water. That is why wider tire tend to spin out in wet conditions....same in snow.

In other words, you put tires on your car depending on driving conditions.
 

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poncho62 said:
The way I see it...The more rubber on the road, the better. Of course,the wider the tire, the less weight/square inch of contact. When it's wet out, there is not as much weight to squeeze out the water. That is why wider tire tend to spin out in wet conditions....same in snow.

In other words, you put tires on your car depending on driving conditions.
This is by far a great issue not many really understand. Conditions of the environment the tire is exposed to during usage and the actual make-up of a tire in its' structure. You can have four individual separate drivers with each a different manufactures' tire, all four cars are identical with the same engine and set-ups are the same. However, the different tires are each of various compounds, and the it is this factor in their compounds that will have the ultimate outcome of which car will finish on top. Softer compounds will allow the tire to heat up and stick to the track more so over a harder compound tire which will actually break traction, due to the rigidity of the tires' build. Harder side walls, being taller and covered with more armor, will be the slowest, due to the fact of the lack of elasticity in the side walls, which actually are a main ingredient when the transfer of power is concerned at race time on a track.
A wide tire is beneficial at the track for several reasons. However, there is one key element over a wide wrinkle-walled tire compared to a street tire at 10.5". The wrinkle-walled tire is actually another gear in your equation during race time. This tire will transfer just the same as your transmission does. it actually will add another gear and can make or break any driver in over acceleration during the launch off the line. This is how the laws of physics can play havoc on the inexperienced driver. You need to understand the ratio in your side-wall stretch for the perfect selection in your first gear launch.
Just 1 inch in height will either increase or decrease your overall run down the track when HP and torque are concerned. A wide tire can actually slow down a car due to the actual HP and final energy transfer to the tires. Too wide of a tire means more drag coefficiency to overcome. Too tall of a tire will change your first gear combination and you loose time to the transition of tire spin/ acceleration and recovery time in hooking up and getting down the track. All in all, due the math before spending the money.

Just as it would be in the desert with sand and all types of obstacles in the path. You would want a taller and heavy armored side-walled tire just for these reasons.

Elemental conditions, being wet, iced, sand, gravel road, or the concrete at a raceway. Everything plays a key factor in what you use.

Good luck all.
 

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I always wondered about the wide tire theory. From what I can tell, it doesn't really change the traction. From my experience riding in cars with wider tires, when you do break traction, the transition between grip and slipping is a whole lot smoother than breaking traction with skinny tires. Like it was mentioned, compound is the deciding factor of "stick" or "slick."
 

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Discussion Starter #5
See the wrinkling of a tire sidewall is another interesting thing. While low profile tires can aid in hard cornering, I have noticed that cars with low profiles seem to loose traction easier compared to a comparable tire with a larger profile. Its like with low profiles, you hit the gas and they let go or they don't there is no minor slipping point. Where as with a normal tire it seems to be a smoother transition. And well I don't have experiance with slicks and other drag tires but I know a 4x4 mudder tire when it spins on pavement its such a smooth transition sometimes you don't even notice.

I don't know its so complicated I mean sometimes theory goes out the window when you take into account minute details such as cornering and sidewall. Road surface imperfections and rocks/sand and stuff.

Like say for example on a real road you have tiny pebbles and rocks. They are going to act sorta like ball bearings so wouldn't a wider tire increase the area of the tire which is actually touching the ground its self rather than all the crap on top? Maybe this is something that seems pointless to look because you would think the pebbles and stuff would be spread out in an even density for a given area. However reality is much more random than that.
 

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True on that one. As you mentioned about your truck tire, the standard width of the tires are designed with a variant in their groves. This is another factor in the grip on the road and off road usage. Taller, or rather deeper groves with designed cross-cuts, basically water directors to help control traction in wet areas. Deeper treads for allowing more concise traction in off road conditions. The simple pebble on the road surface is taken into the design of the tires, to either be over come by the deep treads or actually spat out by the tire. Thus no marble effect.
Then as mentioned with the low profile tires, which are strickly designed for heavy road usage and speed driving. The wider the tire, the greater the surface load distribution onto the road. All-tho it may be wider, does not mean better traction. Tread designs are crucial in this area. Mostly for road conditions and weather.
Now we bring in the new all terrain all weather condition tire. I would rather have a tire with a 6" side-wall over a low profile tire with only 2" side-wall, you have a greater chance of survival on the road with a taller side-wall tire when extreme weather conditions are a controlling factor. The load transfer of power is actually a less aggressive action/reaction with driver and suspension of the vehicle. Sure those low profile tires on the large diameter rims are eye candy, but do not add to the handling of high HP rated car. Too less of a side-wall will hinder the handling at high speed cornering and slide control is out of control, due to the fact of the action/reaction of driver and suspension of any car.

Best example are the Indy style Formula 1 cars. If you look closely at their tires, you will see tires with tall side-walls, some of these tires have more then 12" of side-wall flex action. This gives the cars the greater control on high speed turns, some actually having ability to handle speeds over 150mph on hairy corners. These tires actually have the flex to help control the action/reaction of driver to suspension of their cars.
Less sidewall means less controllable speed in the corners.

So for drag racing at the track, the skinny tires up front cut down on the drag ratio of the vehicle, less area, less load on the surface. Wide tires on the rear for power ratio transfer to the surface. But there is a breaking point on how wide of a tire you actually need when it comes to the actual HP developed and how much stress your ride can handle structurally. A great deal of math for the proper combination to winning the flag.
 

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Discussion Starter #7
A comment on the low profiles. There is sort of a sweet spot in this area, for example if you go too low your car rides like crap and the suspension gets more wear, also the tread doesn't really stick to the road with a bit of sidewall movement that is desired. At the same time, too much sidewall and the rim will roll over the tire if you have a grippy tire and a good handling car. This has happened in a car I was in and it was scary because after the rubber rolls over so much 1 of 2 things happen, 1 the tire comes off the bead or 2 the tire starts to skid. There is a 3rd possibility too but much more rare, once the thing starts skidding it suddenly grabs and then you have the rim rapidly roll the tire, which has enough traction to roll the vehical.

So like I suggested there is a sweet spot here, and I can say that for certain.
 

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ChevyThunder said:
A comment on the low profiles. There is sort of a sweet spot in this area, for example if you go too low your car rides like crap and the suspension gets more wear, also the tread doesn't really stick to the road with a bit of sidewall movement that is desired. At the same time, too much sidewall and the rim will roll over the tire if you have a grippy tire and a good handling car. This has happened in a car I was in and it was scary because after the rubber rolls over so much 1 of 2 things happen, 1 the tire comes off the bead or 2 the tire starts to skid. There is a 3rd possibility too but much more rare, once the thing starts skidding it suddenly grabs and then you have the rim rapidly roll the tire, which has enough traction to roll the vehicle.

So like I suggested there is a sweet spot here, and I can say that for certain.
lol...I have actually had a two tires roll off the rims one night. We were out raising the dead late, I was racing down a cobble-stone road, up and down rolling hills and around lakes down in old Winter Park City, Florida. We came to split section on a winding turn, heading downhill, what a mistake to make. We hit the curb and stood on the outside two tires going around a lake at ~60 +mph. Well we had five in the car and everyone was climbing the high side to balance the car as we headed around the lake. Well we finally slowed down to a reasonable 40mph and finally was on flat and straight ground. When we hit the ground, the car was sliding and then rolled the tires off the rims.
That was an expensive night. Ended by hitting the curb and jumping the car over the curb, rolling it up onto a giant live oak tree. Totaled the car and ate up 60 feet off some dudes lawn. We all survived and took the beer down to the lake and started to get drunk and dispose of the evidence.
Things we do for fun. :thumbup:
 

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Discussion Starter #9
Yeah I really don't like that feeeling when it starts to happen. Then you stop after a few sharp turns and look at the side of the tire and its been used as the contact patch.
 
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