1908 and 1909:
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| Image from New York Public Library Digital Collections |
The 48 HP Model "M" and 38 HP Model "O" Knox race cars can quickly be distinguished from each other based on several visual features:
The Model O has a rear differential; the Model M is chain drive.
The Model O has an unusual tubular front axle beam with a pronounced dip in the center (see bottom picture in ad below); the Model M has a more traditional-looking forged nickel steel axle beam (see photo below of Model M front axle beam).
The operating levers are placed differently.
The front frame rails are shaped differently where the front leaf springs attach.
There are other differences but these are the easiest to spot in vintage photos.
Note that car numbers changed frequently based on assignment by race organizers; both cars raced with many different numbers.
The Model M was primarily driven by Al Denison and the Model O by Billy Bourque.
One newspaper account described the Model O as being "coffee colored" and another described the cars as "twins" which suggests they were both the same coffee color.
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Billy Bourque in 1908 Knox Model O race car, factory promotional photo.
Note to self: Identify date by matching car number to an event date.
Image courtesy of John Y. Hess, Knox Automobile Club of America |
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Racing success was a big part of
Knox's advertising campaign. |
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Billy Bourque and Harry Holcomb in 1908 Knox Model O race car.
Factory promotional photo, 1909 racing season.
Image courtesy of John Y. Hess, Knox Automobile Club of America |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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"Straight line drive" (drive shaft and differential) used on the Model O.
Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
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| Image from New York Public Library Digital Collections |
