Class: Others, Farming vehicle — Model origin:
00:36:45 Minor action vehicle or used in only a short scene
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◊ 2019-02-24 18:43 |
Ab Jenkins' 68 MPH run in 1935. 36:55 - 37:10 |
◊ 2019-02-24 20:02 |
Having read Hemmings’ article, the comments and the linked site I am still little wiser about the way they did this. The one clue is the comment that the tractor had no power for ploughing, which suggests that the gear ratio of the final drive was somehow changed to allow more mph per rpm, or an overdrive fitted to reach the same result. At a guess, an engine output of maybe 50 or so bhp would be enough, the engine looks like a fairly modern ohv type, so presumably that could be wrung out of it somehow. Interesting. |
◊ 2019-02-24 21:20 |
"At first Merritt staged demonstrations at county fairs and such that pitted a steel wheeled Model U against one on rubber in plowing demonstrations. The farmers who stayed to watch were impressed but this proved to be too academic to generate much excitement. Back at the factory he had his engineers modify the gearing of the U to develop the maximum speed possible. His next move was to hire a team famous race car drivers that included names like Oldfield and Ab Jenkins and send them out on a barnstorming tour of the nation’s dirt racetracks." http://theironmule.blogspot.com/2017/12/1949-allis-chalmers-model-u_35.html The engine at first glance looks like a standard A-C unit, as you say the gearing would have to be modified to achieve maximum power at sixty-plus mph versus normal tractor speeds of less than 10 mph. As such ploughing when high power/low speed is necessary would be out of the question with the modified tractor. The 1970s diesel tractors I have a little experience of had a four-speed gear-box running though a high-low supplementary box giving eight speeds; at 2,600 max rpm (max) speeds were between 2 and 14 mph depending on the gearbox and high/low ratio. -- Last edit: 2019-02-24 21:33:50 |
◊ 2019-02-24 22:14 |
Thank you for this. |