suspension/tire questions

I have across a interesting suspension analysis that seemed to be real thorough, but much of the data was based on or derived from this graph:

http://rejsa.nu/im/_garage/1723-new_2009-10-15-1_tire.jpg
The author admits that this graph is from one specific type of tire (a rather old one) but he suggests that most tires are similar enough to use this data.

My question is what variables could change this graph and how would it change?

I expect that a narrow tire would have a narrower curve (a steeper drop off of traction above 0 and below -3), and that tires with more flexible sidewalls might have a wider area of traction at the top of the curve, tires of a stickier compound would simply bump the graph up to higher G’s

These are all guesses but if anyone good info on this I’d love to study it a bit more. Especially if anyone knows what would move the entire graph to the left or right, in other words, in what situation or environment would more or less camber provide with more grip?

I would also think that tread pattern design would have a lot to do with the curve of the graph also. Shitty tread pattern on the inside of the tire is definitely going to affect grip in the -2* and lower section of the graph

ah, good point. Especially asymmetrical tread patterns I assume.

Graph does not specify how the CoF is measured. Is it perfectly perpendicular to the rotation axis or with some kind of slip?

Some variable off my mind would be speed, slip angle, road camber, surface traction, tire compound, tread design and tire construction.

PS. Take a look at the book RCVD by Milliken, you should find all your answers there. Enjoy.

I spent all day yesterday trying to find that book for less than $85 :frowning:

A new one is $100. I say spend the extra $15 and be done with it.

There is a reason why there are no used copies…

I have a copy at the shop somewhere in the collection. I’ll see if I can dig it out this week for you to borrow.

Finally ordered the book. Nice new hard cover.

btw. the article I was reading was this one: http://rejsa.nu/forum/viewtopic.php?t=60154

Man, if you find that kind of stuff interesting, you will have so much fun (and pounding headaches) reading that book. Enjoy! :pop

:excited