On Sun, 1 Aug 2010 15:01:31 +0100, Stimpy
wrote:

Of course, there is an argument that says a properly designed car shouldn't
need 'add-on' wings/spoilers etc fixed or otherwise.


Many cars suffer from increased lift at higher speeds. The spoiler
provides increased downforce to counter this.

The Audi TT (first model) suffered a significant increase in rear lift
at higher speeds. In some markets, but not the UK, the automatic rear
spoiler was standard equipment. In the UK, which has a 70 mph limit,
it was an optional extra, presumably on the basis that it was not
actually needed at 70 mph.

There was some discussion in the motoring press about whether TTs sold
in the UK should all be so fitted, in case they were taken to (for
example) Germany and driven at much higher speeds - some stretches of
German autobahn have no speed limit for cars in good weather.

IIRC Audi UK accepted the suggestion. Subsequently all TTs sold in
the UK had the spoiler fitted as standard.