bentonh@tekid.UUCP (Benton Holzwarth) (08/28/83)
I've just laid hands upon some wind tunnel test
reports, from tests made by Kamei (Wolfsburg, W. Germany),
on their front and rear spoilers. The test vehicle
was a BMW 2002.
They give several figures and a graph, for the front
alone, the rear alone, and the two together. The figures
are described by some german and its english translation.
Front spoiler - (Kamei Type: 4 4220)
Decrease in aerodynamic drag coefficient 'Cd': - 5%
Higher top speed adequate to increase in performance 'P': + 8%
Reduction of fuel consumption '/\FC', combined driving: - 1.7%
Decrease in lift coefficient on front axle 'Clf': - 42%
Rear spoiler - (Kamei Type: 4 4430)
Decrease in aerodynamic drag coefficient 'Cd': - 4%
Higher top speed adequate to increase in performance 'P': + 6%
Reduction of fuel consumption '/\FC', combined driving: - 1.4%
Decrease in lift coefficient on rear axle 'Clr': - 108%
Front and Rear spoilers -
Decrease in aerodynamic drag coefficient 'Cd': - 9%
Higher top speed adequate to increase in performance 'P': + 15%
Reduction of fuel consumption '/\FC', combined driving: - 3.1%
Decrease in lift coefficient 'Cl': - 44%
My Notes:
Beyond the drag reduction, and (small) gas savings,
I've been told there is an amazing performance difference,
especially in stability in cross winds.
/\FC is 'delta'FC, there's no triangle character on
my terminal. 'Higher top speed...' is perhaps their prediction
of top speed based upon the reduced drag. Its ofter difficult
to guess exactly what they mean, after the translation. Anyone
read technical german?
If anyone wants a xerox of the reports (they have some
nicely done graphs (lift vs speed), which I refuse to type
in on my terminal), send me your U.S. Snail address and 50
cents (or two stamps) to cover postage and handling (and my
hassle typing all this in), or within Tek send your mail stop,
and I'll send a copy. It's three pages. Its also difficult
to summarize, so I won't try.
Benton Holzwarth Benton Holzwarth
Tektronix, Oregon 4724 SW Garden Home Rd.
Portland, Oregon 97219
...tektronix!tekid!bentonh