Some cool precision metal components pictures:
Rohr 1996 Porsche 911 GT1, diffuser, tail lamps spoiler
Image by wbaiv
The "diffuser" is the black tray at the bottom that smoothly expands the airspace under the car from the close fit from vehicle to road, amongst the axles, to a height chosen to give maximum downforce for minimum drag, in concert with other aerodynamic characteristics. In some racing vehicles, the airflow at full speed as much as triples the force exerted by weight alone on the tires. The tires can only accelerate a vehicle forward (through engine) or back (by means of brakes), or from side to side by steering, up to basically the same acceleration that applies the tires to the road. Push it down with the airflow and you can turn sharper, brake harder or accelerate quicker. Good trick.
Even better, with reasonable aerodynamics, 7 to 10 units of down force price only 1 unit of drag – that’s named the lift to drag ratio, even if the lift is upside down.
Note "T" pin holding the physique to the chassis.
As you can see above the tail-light, 1-piece back-of-the-auto is carbon-fiber composite, as is the undertray. The only metal here are the exhaust pipes, the red-painted pickup loop bolted to the transmission, the "T" pin, its keeper, assorted fasteners. and a piece of black painted steel strip forming the basket inside the choose-up loop, exactly where the breather catch tank nestles. That tank, each vent hoses, all the body operate, are all plastic parts. The tail lamps are stock 993 things.
DSC_0165