I have a Speedometer 1911 #26, but not the Gears
and the swivel.
Can one of you tell me what gears and what kind
of swivel do I need .
Is there a difference in gears IN the swivels .
I can not find any information about RPM s
in relation to the miles
Bruce McCalley's book: "Model T: The Car that Changed the World", is the reference source you need. Chock full of detailed pictures and descriptions, it has just about everything you could ever imagine on the Model T, arranged by years and systems, including the various speedometers that were used during the production years. Christmas is upon us. You should put it on your list. Jim Patrick
Another source is the Antique Auto Speedometer Book, available directly from Russ Furstnow, who posts on this site, check his profile, his book has lots of info.
The only thing I know about the Stewart 26 is that it takes the 2 1/2:1 ratio swivel and a #22 road gear.
As Dan suggests, the book by Russ Furstnow fills in the information you need. Please contact him.
However, if you are sorting through some components you have for a Model T, the swivel is the 2 1/2:1 and if your application is for a lefthand drive car, the number of the "RHD swivel" is a Stewart "1913", to be mounted on the right front wheel. In the year 1911, that same swivel was a "1800". The road gear is the #22 which is a Stewart 60 tooth 8 pitch and the pinion gear is a 16 tooth. A 48" cable is what you need to hook it up on a '11-'14.
If you have a RHD car the road gear will be on the left front wheel and you will be looking for a LHD 2 1/2:1 swivel, Stewart #1959 or #1953 but the same cable, road and pinion gears.
Stewart manufactured the Model 26 speedometer from 1909-1915 and the drive ratio is determined by the year of manufacture. If your speedometer was built in 1909 or 1910, the drive ratio is a 1:1 ratio. If your unit was built in 1911-1915, the drive ratio would be 2 1/2:1. You can determine when your speedometer was manufactured by the letter preceding the serial number found on the dial face. The road gear will always be a 60T8P gear and the pinion gear will always be a 16T8P gear on your Model T. I hope this helps.
Can't you tell by the odometer? My early 26 with odometer in individual windows takes 1:1. The 26 with later drum style odometer I have is 2.5:1.
At 65-70, the 1:1 cable is spinning pretty fast.
The 1909-1911 Stewart speedometer dial face had "port holes" for the odometer, while the 1912-1915 used rectangular openings. Stewart changed from the high speed drive (1:1) to the low speed drive (2 1/2:1) in 1911, so all 1911 speedometer had port holes, and used the low speed drive. A 1911-1915 head can be damaged if it used with a high speed drive. Hope this helps, Russ Furstnow
Thank you all for your help !!!!
Here is what you need. Note that in 1911 the steering arm was not provisioned for the speedometer drive mounting, it clamped on as shown. The speedometer drive assembly and all attaching parts would have been brass plated. Some of the parts on my car are painted black which is not correct. The cast iron gear would have been brass plated too.