So I have been watching the official WRC channel on Youtube.

And I have noticed something rather odd from the slow-motion videos they have been putting up. When the cars jump and the wheels loose their load the wheels have positive camber.

This would indicate that they don't use double a wishbone suspension system. What do they use and why?

For those interested a link to the channel:
WRC Youtube channel link

WRC cars use MacPherson struts, so when the car jumps the wheel pivots around the lower control arm (in blue).



You can see the lower control arms here:



It looks quite dramatic on a gravel setup because of the high suspension travel and low camber.

Woah, I actually didn't know they used Macpherson, I thought they'd moved on to something a bit more advanced. like some strong multilink wishbone construction

Something like this.

Well I assume WRC choose to use McPherson struts instead of a more modern set-up.

Maybe the Older system gives more travel?
I also assume it would be easier, or faster to repair?

I think they're still limited by what is homologated in the road cars.

Quote from Chrisuu01 :

Well I assume WRC choose to use McPherson struts instead of a more modern set-up.

Maybe the Older system gives more travel?
I also assume it would be easier, or faster to repair?

Doesn't matter, it's all about making the control arm connection longer, add a longer spring and damper, just look at trophy trucks

Quote from Chrisuu01 :

This would indicate that they don't use double a wishbone suspension system.

This does not indicate that. You can pretty much have the travel/camber curve you want with a double wishbone setup. You just have to mess around with arm lengths and attachment point locations.

Quote from PhilS13 :

This does not indicate that. You can pretty much have the travel/camber curve you want with a double wishbone setup. You just have to mess around with arm lengths and attachment point locations.

But wouldn't that give the wheel positive camber al the time?
Even under load?

Quote from Chrisuu01 :

But wouldn't that give the wheel positive camber al the time?
Even under load?

No. Why would it? Only equal length, parallel wishbones will give zero camber change over all of the travel range. As soon as the wishbone are unequal and/or not parallel you can have the wheel do what you want.

Here : Negative camber under load in red. Positive camber unloaded in blue.



Don't get me wrong you will never see that awkward setup. I can't think of any reason why anyone would want a double wishbone to behave that badly but they certainly could if they wanted to.

Quote from tristancliffe :

I think they're still limited by what is homologated in the road cars.

Only Group N cars(which is about to die anyway) are homologated to road cars. Fiesta WRC car's one corner(damper, arms etc) costs about 2 500 euros btw...

To keep the costs down at least the Mini WRC uses the same McPherson's on all four corners

Quote from ACCAkut :

To keep the costs down at least the Mini WRC uses the same McPherson's on all four corners

Which is probably one of the reasons it never got any decent finishing postition.
Also Kris Meeke was probably not that good of a driver, compared to the likes of: Ogier, Loeb, Latvalla

Quote from Chrisuu01 :

Which is probably one of the reasons it never got any decent finishing postition.
Also Kris Meeke was probably not that good of a driver, compared to the likes of: Ogier, Loeb, Latvalla

The DS3 also uses McPherson struts. As did the C4, Xsara, Fiesta etc. You get the point.

Here are the specs from the M-Sport website for the Fiesta.

Quote :

Front and rear: MacPherson struts with Reiger external reservoir dampers, adjustable in bump and rebound. Fully adjustable fabricated steel links. Front and rear anti-roll bars. Machined aluminium uprights.

http://www.m-sport.co.uk/index ... y-cars/ford-fiesta-rs-wrc