CASE-STUDY: Mercedes-Benz C-111 / III (Cd 0.178)

[NeilBlanchard]

Some additional pictures:

[Peter7307]

There was talk of making a road going version using the 5 cylinder diesel to replace the 4 rotor rotary of the experimental cars and Mercedes did extensive research and published quite a few papers on the idea.

Other demands meant the project was halted but the 5 cylinder moved to the production line and was used in the W123 series cars initially (1976 to 1985) and other variants later.

There were also scale models made in die cast in 1:18 th scale of the road going prototypes and some were available from MB dealers at the time.

Pete.

[winkosmosis]

Is that a pointy nose I see?


Why does it have louvres instead of a smooth rear window though?

[theycallmeebryan]

Originally Posted by winkosmosis

Is that a pointy nose I see?


Why does it have louvres instead of a smooth rear window though?

My guess its to cool the engine that is probably located behind the cockpit?

[NeilBlanchard]

You can see through the louvers (probably) very well. It sure looks like the cooling is in the front.

At the speeds that cars run at, a pointy nose is not required. Look at the Schlörwagen and the Boxfish...

[jimepting]

Phil, bit hard to tell. Was the radiator intake below the stagnation point on the front. I see that the engine compartment was vented to the windwhield "pocket." Looks like a superb setup to minimize radiator drag and windshield stagnation.

[aerohead]

Originally Posted by jimepting

Phil, bit hard to tell. Was the radiator intake below the stagnation point on the front. I see that the engine compartment was vented to the windwhield "pocket." Looks like a superb setup to minimize radiator drag and windshield stagnation.

I'm away from home so I don't have my own photos to look at,and I can't remember ( hey at my age I'm authorized now ) but it looks like the area below the lowest slat is open right at the stagnation point,and then they've opened up the area,snagging more air with the additional slats/louvers.
Remember,this was a 'track' car,and operated at W.O.T. for hours/days at the Nardo,Italy track.
Daimler would have been very concerned with engine cooling,operating at the ragged edge for so long.
In day to day operation,the car would never require this amount of cooling air.
At Bonneville,My CRX ran with the temp gauge nearly pegged,so I know this is an issue.
As to the cooling system itself,it is exactly what Walter Korff was pushing in 1963,and it also happens to be what put Wunibald Kamm on the map.The energized flow going over the windshield helped to keep the air from stalling which allowed his roofline to work.
And a safety note: Should a radiator or AC condenser explode ( I've experienced this 3-times ) the hot gases from the cooling system will hit dew-point on your windshield,condense,blind you,and you will in all likelihood crash.The gases from the ruptured AC unit will outright blind you.
It's my opinion that the safety risk of this type of mod overshadows any aero benefit.
Maybe better to move the heat-exchangers rearward as in the Ford concept cars.

[hypermiler01]

I found another great thread on this car, including press release data directly from Mercedes.

C111-IId and C111-III details from Mercedes