holycow

Hey guys,

So I kind of confused about how a negative camber works on either the front or rear end of our touring cars. I have read 100 or so "pro" setups on numerous cars, and MOST drivers run between -.5 and -1.5 camber on their cars. But I would like to know why?

Now before you say "oh what a noob", I do know (or think I knew) why neg camber is run, and am familiar with the concept in both RC and in 1:1 racing, which I personally do.

I thought, that a negative camber is run because when a car turns and weight of the car is shifted to the outside, the outer two tires will tend to stand up, and shift in a positive direction. The point of starting at -1 or whatever, is so that when the car is in a hard corner, and the tire stands up, it will be at 0 degrees at the height of lateral force, giving the tire the greatest amount of contact patch as possible. Please correct me if I am wrong !

BUT... I was setting my Schui misison up last night with my Integy setup station, and was looking at all my settings, and what I noticed was that no matter what I did to the car as far as pushing on the suspension, left right, wheels turned left right, the degree of camber on the outside of the car always went in a negative direction.

Example, I set the car up at -1 degree all around, as a starting point. I turn the wheels of the car to the left, and press down on the right suspension, simulating a left hand turn. my outsite tire's camber doesn't go from -1 to 0, it goes from -1 to -2, or -3 (i forget at the moment), effectivly DECREASING the contact patch. It does this no matter where I set my caster, and no matter where I set my camber.

What am I missing?

Thanks for any info from you pros.

utieh

iTrader: (3)

you have to play with the camber links position on the rear/fron hubs and on the shock towers, it will affect how the geometry of your suspension works during cornering.
I am not an expert too so I don't want to tell you more (don't want to say something wrong...)

ZER01

The more negative camber the more friction you are creating on the "contact patch" of the tire in whatever degree you are running, if you are running 2 degrees negative camber you are creating more friction on the contact patch of the tire MORE than if you were running 1 or 0. If you create too much friction the tire will break loose, "hop" or "chatter" which resilts in whats called traction rolling. Usually camber is your last tunning adjustment.

holycow

eehh?? No, I think the MOST friction would acheived at 0, when the entire surface of the tire is holding equal weight.

Well I am not even sure I understand what you typed. I think you have this backwards. Take the tire out to -90, and you are going to be riding on plastic... acheiving 0 traction. The more surface of rubber touching surface of asphault, the more traction. This would be achieved at 0 degrees.

Ok... but im still not sure that has answered my question. Are you saying that people degrease their camber in order to REDUCE traction? As in:

0 = traction
-1 = slightly less traction
-2 = even less traction

fatdoggy

Your missing momentum, when your car is moving and you try and corner, the car pushes all that foward motion onto the front right or front left wheel, putting alot of presure on them. Just pushing down on one of the 4 corners isn't an acurate representation of what happens when your car corners at 25 miles per hour. My guess is right now your running caster on your car. Caster changes your camber as your servo reaches it's endpoints, more caster gives you less initial turn in but more later in the corner and less does the opposite. Now set your car to zero(or close to caster) when your servo goes to it's endpoints the camber shouldn't change at all.

fatdoggy

IMO camber should be settup one way, even tire wear. I don't care what other people do, if your tyres are having the most contact with the surface your running on, you have the ability to push harder and faster and in the end do better. No if you have too much grip your can easily get rid of it through the suspension, you don't have to jump straight to adjusting camber.

holycow

I understand what you are saying, but it still doesn't lign up. I am aware of how outside momentum changes how your car is sitting at any moment around the corner, even if the car is leaning ALL the way to the ground, and I pull on the car as hard as is reasonable, there is NO WAY the camber can possibly get anywhere NEAR 0. With the tiny bit of caster I am running, if the car leans at all, regardless of what momentum is put against the car, you are still looking at 2 or more degrees of (-) camber.

holycow

By the way, I am basically running between 0 and -.5 degrees of camber, and my wear on the tire is ALL the way in on the inside rim of the rubber, right against the inside sidewall.

fatdoggy

Tires do deform that's how they find grip, if you have rock hard tires that don't move your not going to have any grip, however if you have soft tyres they adjust there profile as they run along the track surface. Do this, find something flat and high traction, now to simulate cornering you need to push outwards as well as down on the front left or right shock. I just tested this and my camber(on the outside wheel) goes very close to 0 degrees.

teamAE

Also on the shui at socal run the camber link in the bottom hole front and back. The car feels very very consitant with this. I can help you out more in person next sat I will be there.

holycow

I am running Take-Off C27s, a 2 on a 1-4 scale of hardness, so they are relativly soft. I find them to be a good allaround tire. that hold traction most of the day, on most surface temps. I do have plenty of traction as far as I can tell, I just like to have all the information, and am looking for the perfect setup.

I can crank my steering to the end of my servo throw, and pull/lean the car towards that outside corner, and the camber doesn't go in the pos direction.. only neg. I think this explains why I have VERY inside tire wear. I have almost no wear on the outside of my tire.

I wonder if I need some help from some Schui pros?

fatdoggy

This is probabely because your not using the right roll centers.

holycow

I dont think so. my suspension can only travel ALL the down on the outside...

I am running:

Schui Red springs all around (medium)
AE 80 weight oil with the 2 hold piston (what most pros setups run)

Front sway on
Rear sway off

Its actually a pretty moderate neutral setup actually. But none of these things change how camber changes in a lean.

fatdoggy

teamAE hit it on the head.

I editted my post, sorry about that. It's your roll centers, these change what your wheel does when the suspension compresses. You can have it setup so that the wheel gains or looses camber as the suspension compresses. That's all I know as I don't have this adjustment on my car.

holycow

Well shoot I bet that is it... TeamAE, what is your name again? Lets hook up on Sat. morning at socal and maybe you can help me out a bit? I will be there at 10am sharp, and usually pit closest table to the register, on the dirt side.

Brandon's the name