I'm also interested in the cross tyre setup. What are the pros and cons? I understand the drivers have a limited amount of tyres per rally so sometimes that's what they have to do. But how much does the diff balance it out?
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I'm also interested in the cross tyre setup. What are the pros and cons? I understand the drivers have a limited amount of tyres per rally so sometimes that's what they have to do. But how much does the diff balance it out?
If I remember right it was Juho Hänninen in 2011 Monte Carlo who used it first (or at least it was first widely discussed case) when Škoda team (and Petter Solberg) fucked-up tyre choice and lost the fight for victory there. He used it out of necessity and it worked much better than let's say two winter tyres in front and two slicks in the rear.
I believe the main rationale lies in the fact that limitted-slip differential helps to bring overall grip level of the axle closer to the level of the better wheel. In that case an axle with only two wrong tyres benefits in no way from having LSD in between. Therefore if You have two better tyres it's better to place one in front and one in the rear (cross) and by that enhance a bit the grip on both axles instead of having one good and one useless.
its just that 2 good wheels on the front give to much oversteer, and 2 good wheels on the back too much understeer. so they use on wrong wheel and 1 good wheel on each axle, which gives a more stable feeling.
the only reason they do that is because they can't carry for spares in the boot.
some close photos from yaris and new canards and front wing from https://twitter.com/Traxx_WiF/media
https://pbs.twimg.com/media/DSs9QKfX0AAJBTW.jpg
https://pbs.twimg.com/media/DSs9QKoXUAA8QPR.jpg
https://pbs.twimg.com/media/DSs9QKqXUAAkRQ3.jpg
Those are still prototype parts, just saying ;)
When do the current WRCar regulations run until?
Agree on all points. Now that more detailed pictures are showing up online, it's even clearer what they did. I particularly like the outlets towards the side of the car on their new front bumper. Pre-2017 cars all had this type of openings on the side, which help manage the air around front wheels. For 2017, the tech reg didn't appear to allow this treatment at first... But clearly with some clever thinking, it's still possible. Good for them! There are other details which are probably very difficult to photograph. Maybe they got some help from the aero department in Cologne? :D
Interesting. The cross tyre setup was a new concept for me when I joined WRC. I do recall the WRC TV commentators were discussing the merits of left-to-right mix, instead of cross. Apparently this could give them more confidence because the car will behave more predictably, albeit at different grip levels left and right.