Quote:
Originally Posted by zu!
I read somewhere that some of these guys have used Coroplast as a kind of under-engine cover. The theory was, that the engine compartment was this large sail that trapped air or something like that and shielding the engine bay from the wind turbulence below would make for some good mileage gains. 
This got me thinking about doing that. I mean, it would be non-intrusive, in that nobody would know unless they got really intimate with your car  . With some strategic folds and bends to the coro-shield, one much-desired side-effect (for me at least) would be the consolidation of all the little drips of oil to ONE drip that could easily be controlled by one sheet of newspaper, instead of the many I have all over my garage floor  |
MB thought the same thing, thats why the next model after the W123, the W124 has belly pans. Even my W126 with its belly pans on is pretty smooth underneath. Everything from the drive shaft to the suspension is kind of tucked up into the car.
The new cars are pretty freaken streamlined underneath, they really spent some time in a wind tunnel. However I think the idea is to lower noise levels, and to suck the car down to the autobahn at 150+ mph. MB claims that they improve engine cooling as well.