Camber and Grip

[Slow99x]

Being in the tire business I see alot of tires that were replaced due to improper care. Tire prices for larger tires are going up and most of the replacements on tuner cars can be avoided through proper alignment. I do agree that toe setting is very important but camber can not be ignored. Proper camber also alows for a larger contact patch on the tire as well as putting the contat patch where the tire was designed to make the most traction, in the center of the tire. This alows for better launches but also causes a slightly higher rolling resistance due to the larger contact patch. It wont be noticible in your top end but gas milage may suffer slightly although I have yet to meet a DSMer that is really worried about milage. So spend the money on a camber kit and an alignment so that your tires are safer as well as freeing up some cash for other mods instead of having to buy tires all the time!

 

[jtmcinder]

Proper camber also alows for a larger contact patch on the tire as well as putting the contat patch where the tire was designed to make the most traction, in the center of the tire.

How sure are you that a square inch of contact patch in the center of the tire produces more grip than a square inch somewhere else? Are there assumptions that must be met for this to be true? Does it matter if we are talking about lateral or longitudinal grip?

- Jtoby

 

[Slow99x]

I am talking about both. tires are engineered to have a certain tread design for a reason. Racing slicks are an exception to this because there is no tread. If you look at most directional tire designs you can see this. The center of the tread is ideal for forward traction and the shoulders are for cornering. There are tires that are designed with different compounds in different sections of the tire that optimize this even further. If you have excessive camber so that the vehicle is putting force on a part of a tire that was designed to do something else then the results are not going to be the best. There is a tire on the market that is constructed at an angle so that even if it is cambered in at the top, the tread makes full contact with the road. This tire is the NeoGen by Nitto.

 

[wret]

I am talking about both. tires are engineered to have a certain tread design for a reason. Racing slicks are an exception to this because there is no tread. If you look at most directional tire designs you can see this. The center of the tread is ideal for forward traction and the shoulders are for cornering. There are tires that are designed with different compounds in different sections of the tire that optimize this even further. If you have excessive camber so that the vehicle is putting force on a part of a tire that was designed to do something else then the results are not going to be the best. There is a tire on the market that is constructed at an angle so that even if it is cambered in at the top, the tread makes full contact with the road. This tire is the NeoGen by Nitto.

I hate to gang up on you but I’ve got a couple of questions.

Road tires are designed and constructed for an extreme variety of terrain; rough/smooth, wet/dry, straight/curvy, level/inclined, etc. How does a tire know if it is mounted with -2° of camber or you are driving on a 2° crowned road?

And when a tires’ tread is completely abraded due to improper camber, and the tire is slick, does it stop wearing?

On BMW Z3, where the factory camber specifications extend beyond –1° in the front and past -2° in the rear, why do BMW technicians warn you of possible premature tire wear if camber is too close to zero?

It’s clear you are trying to be helpful, and God knows there are a few tuners that could use some alignment advice, but It's been proven that the optimum handling formula includes a little negative camber, and not necessarily at the expense of tread wear.

 

[jtmcinder]

OK, if I'm following the revised version, you're saying that one square inch of center is worth more than one square inch elsewhere when we're talking longitudinal, and one square inch of shoulder is worth more than one square inch elsewhere when we're talking lateral, and that this is due in large part to the design of the tread.

- Jtoby

 

[Slow99x]

Correct. If you look at a tire like the Michelin Pilot Sport A/S you can actually feel a difference between the center of the tead being softer than at the shoulders.
As for the other question, every sports car has some degree of negative camber and on some they even have toe that is not at zero. The earlier year Acura NSXs actually had a recall on them because this was so excessive from the factory that that Honda gave NSX owners three sets of tires. I am not saying to set your camber to zero but at least set it to factory or close to prevent tire wear.
The tires will wear to the steel belts and eventualy blow out.

I understand that we drive sports cars and that tire wear is something that we all have to deal with if we drag race, autocross or just drive around on the street. Our tires will wear faster than your mom's minivan but on average our tires cost twice as much as your mom's minivan. What I am trying to say is if you are going to lower your car fix the alignment! Don't leave it as is after you slam it 2 inches. Even if you don't lower the car, everyday wear and tear moves the alignment. Have your tie rods and ball-joints inspected for movement. There is an alignment for diferent types of motorsports like autocross, rally,etc.. but most of us drive our cars on the street and some of us live in an area where it snows. The center of the tire is the best place to get traction because the tires were designed to work that way. If you have any dispute about this, feel free to contact any tire manufacturer to ask if this true. You don't have to beleive me but I do this for a living every day.