Diesel Exhaust Shape?
Answers:
I think its for smoke deflection, Diesels all smoke to a lesser or greater extent. Think about it, if you had a straight exit pipe, that will blow the smoke directly out to the vehicle behind, if its a bent down design it points to the road, thus dispersing the smoke better. The reason also, that most have twin pipes is for better breathing. I don't think its a requirement in the UK! Hope this helps!
Does anybody really care?
Don't know but in Australia they shouldn't point down because it is possible that on a dusty road they will cause decreased visability. All exhausts (even in petrol cars) must be horizontal or (on a truck) pointing up.
Maybe they point them down so that they can't get water in the exhaust from rain?
because of the black smoke they sometimes emit
With race cars, turning the exhaust tip downwards helps you to conform to noise emission reqiurements.
because of disgusting smoke it spews out
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