micro "mud" flaps spotted

[Piwoslaw]

Originally Posted by focus1.6uk

I recently spoke to a senior engineer who worked on the Astra GTC and he confirmed this; they are for EU homologation concerning coverage of the tyres, not for aerodynamics or road spray control.

Could someone explain?

[Sven7]

Laws state you can't have the wheels/tires poke out completely outside the fenders. Further, the tires can't poke past any part of the body over a certain amount. They never had a problem like this before because no one cared much about wheel fitment. Now having the wheels flush to the fender is all the rage (see, "hellaflush", "stance movement") and OEM's want to get in on it. Problem is, the kind of fitment car enthusiasts get is not legal to produce from the factory. Therefore they put these tabs on to "cover" the wheels when viewing at a certain angle, so the tires technically aren't protruding from the fenders.

You can see the tires stick out farther than the bottom of the bumper. The bumper tapers in but the tire is vertical. The tire "tucks" under the fender at the top and "pokes" out at the bottom.

The OEM's can't legally produce something that takes this characteristic too far. Putting those tabs on visually "covers" the tire so they can push it out farther with a lower offset wheel.


Here you can see it in real life:

[Sven7]

The wheel/tire fitment goal is something like this: low, flush


Tabs let them cheat the laws into having lower offset wheels stock. I will bet it's mostly designers like me b****ing and whining to have better wheel fitment, and the lawyers coming back telling them it's not possible. Then the designers come up with some little cheat that allows both of them to get what they want: a cool looking car they can legally sell.

[Rokeby]

The idea that the little flaps are reg cheaters is interesting.

I have to wonder how far it can be pushed by dedigners/builders
and accepted by buyers/drivers.

In the C1 class canoe, the hull has to be a certain minimum
width across at the waterline. But one of the factors in theoretical
hull speed is width. Enter this within the rules, but very difficult to
keep upright, result:



FWIW, "tracking" or ability to keep to straight line is excellent.

[euromodder]

Originally Posted by Piwoslaw

Could someone explain?

Most likely some part of the directive states "no part of the tyre may be visible from above" or " no part of the tyre may stick out from the body work".

These flaps are positioned where the bodywork toes in vertically and horizontally.
The result is that when seen in plan view, the extreme edges of the tyres could (barely) be visible - so they need covering.