Ambler Quick Change Gear Box used in midgets in the 1940's-50's is anyone familiar with this, I understand it had sun gear quick change in the transmission, to in the rear as in most quick change units. I have avery early midget last run in 1947, driven by Raplh Moody of Holman - Moody fame. He raced the car in Seeking MA area as the start of his racing career. You can call anytime to discuss jerry 860 655 8682
There is a young man named Dennis on here that can enlighten you on the subject. His hamb name is "Frames"
What do you want to know? Most early midgets, if they had a gear change box, used one of perhaps 25-50 different available units. They were usually incorporated with an in/out box and some were made using Model A Ford input shafts and high gear sliding coupler. The Ambler was an internal ring gear of 48 teeth and to change ratios you changed only the input gear that ran against the internal ring gear. The gear box slid up and down in slots on the front mounting plate to compensate for the different input gear diameters and achieve proper mesh. Thus they were often called "slider boxes". Other designs used gear pairs and were called "over and under boxes", but also used the sliding design to accommodate the difference in gear diameters. The term "Quick Change" as cast into the Ambler box is a misnomer. There is nothing quick about changing gears as generally the box slides back to provide an access to the gear, but then the out put shaft hits the U-joint cross and even if you can get your hand squeezed in there, lots of luck trying to the new gear in and the very shallow spline lined up so it slides in position. It was easier for me to loosen the rear axle mounting and slide it back slightly. Read most of page 109 on the HAMB "Vintage Cageless Midget Picture Thread" for more info and photos.
I own the original "core boxes" to cast Ambler Quickchange rear end housings. They used Model A components. Unfortunately I have no drawrings or paperwork for them, I have pulled a couple of castings from them & they turned out great. Would love more info on the rear ends also. I have seen the Ambler boxes & I believe Ryan Newman has a midget with one in it. Cheers Tony
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