a trick i often use is to pump up the rear tires to about 45psi for the test.when car sits on dyno there are two bags created with two dyno rollers and this adds to the drag.higher tire pressures makes a measurable difference.

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David S Poole
European Performance
Dallas, TX
4696880422

"Fortune favors the prepared mind"
1987 Mercedes Benz 420SEL
1988 Mercedes Benz 300TE (With new evaporator)
2000 Mercedes Benz C280
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