Negative Camber yes/no? How much ?
02-19-2004, 11:18 AM
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Negative Camber yes/no? How much ?
As I am starting to track I have been advised to add some negative camber to my wheels . ( I could be considering in a first stage to use the same set of tires for travelling as well as for tracking ).
The outside of my P0's Assimetricos are nearly slick and the middle and inside are ok.
Funny enough, one Rennlister told me that this could decrease straight line braking performance and another , referring to Michelin's advise, said that this would improve straight line braking (!!?). Both told me that this would help to add some more life to the tires as it would even their wear.
Mark, from Baltimore warns me that camber should be adapted to different situations of a track/car, etc.. . For his993, he runs on MPSC's 1.1 degrees of neg camber in front, 1.5 degrees in the rear.
What is the forum advise. I wonder on the negative effect in
a) regular wear of the tire and
b) stability in straight line. ?
If positive, what would be the recommended camber for a standard 996TT with P0's assimetricos ?
The outside of my P0's Assimetricos are nearly slick and the middle and inside are ok.
Funny enough, one Rennlister told me that this could decrease straight line braking performance and another , referring to Michelin's advise, said that this would improve straight line braking (!!?). Both told me that this would help to add some more life to the tires as it would even their wear.
Mark, from Baltimore warns me that camber should be adapted to different situations of a track/car, etc.. . For his993, he runs on MPSC's 1.1 degrees of neg camber in front, 1.5 degrees in the rear.
What is the forum advise. I wonder on the negative effect in
a) regular wear of the tire and
b) stability in straight line. ?
If positive, what would be the recommended camber for a standard 996TT with P0's assimetricos ?
02-19-2004, 12:22 PM
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I'm sorry if I added to the confusion. Did you think I was the one who said straightline stability would increase as more negative camber was added? If so, maybe go back to that post and reread what I said. When posting the info from the Michelin guide, I was trying to speak in generalities. I found the guide to be very helpful and wanted to pass on the wisdom. I guess my first question is how many miles did you put on the Pirellis? If the outside edges are wearing, were they worn out by your driving style or the PO's?
If you wore out the edges, then it looks like you need a bit more neg camber dialed in. I posted the info from the Michelin guide (in a previous thread on the Wheel and Tire forum) to inform you of the trade-offs you'll be making as you start adjusting the camber. The Michelin guide seems to be directed at the hardcore race who is making camber changes at the track, taking tire temps immediately after a hot lap, in other words, written more for the people who are dealing with the science of racing as opposed to the art.
Still, their warnings are something to keep in mind as you make changes.
Re the straight line stability, if you think about it, the flatter your tire is to the road, the better grip it has, whether you're going in a straight line or cornering. In a straight line, you want the tire to be parallel with the road surface. But a tire that is set up to be parallel to the road in a straight line will, in a corner, be apt to lift one part of the tread, forcing you to lose some cornering force. If you dial in neg camber to make the tire "more parallel" under cornering, you may be adding so much neg camber that your tires are no longer parallel while NOT cornering and driving in a straight line.
I don't think too many of us will be making camber changes at the track. My camber settings are pretty mild but I may dial in more neg camber to get more grip out of the tires. Presently, my tire wear is darn near perfect across the board, but what I really need to do is start using my pyrometer after a hot lap and measure tread temps on all four tires.
Do you have a good race shop out there? If so, maybe they can recommend a compromise setting for you.
Good luck! I'm sure other people will chime in here. Again, sorry if the info from the guide was confusing.
If you wore out the edges, then it looks like you need a bit more neg camber dialed in. I posted the info from the Michelin guide (in a previous thread on the Wheel and Tire forum) to inform you of the trade-offs you'll be making as you start adjusting the camber. The Michelin guide seems to be directed at the hardcore race who is making camber changes at the track, taking tire temps immediately after a hot lap, in other words, written more for the people who are dealing with the science of racing as opposed to the art.
Still, their warnings are something to keep in mind as you make changes.
Re the straight line stability, if you think about it, the flatter your tire is to the road, the better grip it has, whether you're going in a straight line or cornering. In a straight line, you want the tire to be parallel with the road surface. But a tire that is set up to be parallel to the road in a straight line will, in a corner, be apt to lift one part of the tread, forcing you to lose some cornering force. If you dial in neg camber to make the tire "more parallel" under cornering, you may be adding so much neg camber that your tires are no longer parallel while NOT cornering and driving in a straight line.
I don't think too many of us will be making camber changes at the track. My camber settings are pretty mild but I may dial in more neg camber to get more grip out of the tires. Presently, my tire wear is darn near perfect across the board, but what I really need to do is start using my pyrometer after a hot lap and measure tread temps on all four tires.
Do you have a good race shop out there? If so, maybe they can recommend a compromise setting for you.
Good luck! I'm sure other people will chime in here. Again, sorry if the info from the guide was confusing.
02-19-2004, 01:20 PM
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Mark, once again thank you very much for your kind and extended advise. I think that I am begining to understand the basics.
Years ago ( many, many, years ago ) I raced ( in European Rallies ) with a Mini Cooper against....Porsches !! I could beat them sometimes ( only going downhill ). At the time my tires had a lot of negative camber. I just followed my mechanics advise and drove as fast as I could !! I would give them my feedback and they readjusted the whole thing. I will follow your advise and try to find a good racing shop and see if they can be of any help. Thanks again.
Years ago ( many, many, years ago ) I raced ( in European Rallies ) with a Mini Cooper against....Porsches !! I could beat them sometimes ( only going downhill ). At the time my tires had a lot of negative camber. I just followed my mechanics advise and drove as fast as I could !! I would give them my feedback and they readjusted the whole thing. I will follow your advise and try to find a good racing shop and see if they can be of any help. Thanks again.
