Poor guy's Air Deflector:
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Air would hug the roof and go down between the cab and shell, creating a horrible din.
As you can see, the air now flows over the gap.
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You can see how the cab aerodynamics work against streamlining.
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Two different size of hose held in place with 3M Painters Tape.
Rain hasn't bothered the tape used in this temporary experiment I did a year ago.
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