
Originally Posted by
Captain_Rightfoot
.34 is nearly twice again .22. It's ** really ** hard to get below .3 if you have a ICE car. The problem is not the top of the car - it's all the mechanicals underneath hanging down in the air.
The Lotus Elite from 1959 was ground breaking at the time. It was said to have a cd of .29. They enclosed basically all the mechanicals up into the fiberglass body. It allowed them to go uncommonly fast with a 1100cc fire pump engine.
And in 1955 Citroen was, from memory, 0.34 - and this was what it remained actually on the road and at all loads, not just in the wind tunnel, thanks to self levelling remaining at the same attitude, with the smooth underbody broken only by the exhaust pipes, with the muffler recessed into the body, and the exits for engine and brake cooling air, which were designed to support rather than break up the airflow under the vehicle. Changes to the nose in 1967 improved this further.
It is not necessary to have mechanicals hanging down in an ICE vehicle - just convenient for manufacturing (and repairs!).
John
JDNSW
1986 110 County 3.9 diesel
1970 2a 109 2.25 petrol
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