What effect does negative camber have in the dirt?

[chimchimm5]

On tarmac, Subies need neg camber; from about -1.5 (front) on a daily driver that sees some track to -2.5 and beyond for more serious track usage.

What affect (if anything significant) does negative camber (front) have in the dirt?

I'm guessing that it doesn't have much effect as the patch is almost never "flat" and the suspension geometry is constantly going up and down. And that the tread pattern matters more. Perhaps harder packed courses might favor more neg camber? Dunno... just appealing to the experts/experienced.

Would a wider (front) track of say 10mm be much more important than say a -0.5 degree of additional camber?

[Stockline]

The amount of camber you want to use is to offset the weight transfer of the car around a turn, and creating the largest tire contact patch to the road. Track cars have lots of grip, which equals more weight transfer and more lateral G's. Therefore they need more camber to offset the forces pulling the suspension essentially out of grip.

As for dirt, you want to have the most symmetrical setup you can for the changing conditions you come upon, unless you know all the stages until your next surface are hard, hard packed dirt, I would leave them as close to stock as possible for best results.

The best example of how camber affects your car, watch a few laps of nascar... if you manage to catch a caution: the low speeds of the cars will show off how much negative camber they are running 3-4 degrees static. But once you see them at speed they are close to 0 when they corner (you see some on the straights) but thats due alot to the aero and the G's that they pull on those banks.

Hope this helps a bit

The short of it: Rally has too many variables and too many changing conditions to be able to set a static camber to match conditions, alot like a road race car you want the symmetry to be there to produce consistant results through rightys and leftys no matter the degree of apex.

[pigpen]

I am not an expert, but I suspect that you basically want to add enough static negative camber to keep from going to positive camber around bumpy turns. if you are at stock ride height with only stock adjustments, I'd just try to get it maxed out, which won't be very much.

but there should be quite a few people on here with some actual experience at different alignment settings in the dirt...

[SoCalBoomer]

It depends on multiple things - but the primary thing to think about is your tire.

When you go around a turn, your outside tire takes most of the force and it deflects - to a greater degree on asphalt, but I've taken and seen videos of dirt tires deflecting quite a bit.

We use negative camber to offset this deflection - i.e. as the tire deflects or rolls inward (imagine with me) it actually rolls so the bottom patch is close to flat.


How does this apply to our tires? Well, it depends a LOT on the sidewall.

Rally tires with stiff sidewalls don't deflect much so you won't get as much effect and you don't need as much negative camber.

Snow tires which typically have very soft sidewalls can benefit from negative camber.


Now - how effective is it? I notice it quite a bit on my Neon's rear tires. I'm running too much, but I definitely notice the difference between 0deg and about -2deg. YMMV - I don't know how it will affect Subies. . .

[A1337STI]

i ran -1.8 front and -1.4 rear with a 1/16" toe out up front at Rally Idaho . Felt about right. my tire size is 165/65/13 with a wider tire a bit less neg camber would be okay. I'll probably back down to like -1.5 / -1 at gorman because its much rougher and i'll be more worried about forward bite , and braking bite, which go away as you start to dial in camber (positive or negative) ....... ..

i found some WRC principle setups to help me with a 'starting point' and i'm trying to tinker with it.. trying to find what's optimal

I've tried -3 before and while that felt awesome on pavement it felt like too much on the dirt (even though cars do get a fair amount of body roll even on dirt roads) it really really ate into my forward bite (though i'm just a fwd car)

[SoCalBoomer]

(though i'm just a fwd car)

bite your tongue! :D