Scimitar Gearbox to Type 9 Conversion

Just as many other children did in the 1970’s, I looked forward to my weekly helping of The Professionals on Sunday night.  Unlike many children, however, a good deal of my thoughts were devoted to making things on lathes and milling machines and so it was with some bewilderment that I witnessed Bodie reflect (in a not remotely camp manner) with Doyle that the risks of their job were “better than standing by a lathe all day”. Adulthood of course brings with it entirely new perspectives and I discover that I have no wish to stand by one of my lathes all day, watching it carve chunks out of a large lump of steel plate which is becoming a Type 9 gearbox adapter.  One of the best aspects of producing a bellhousing register at one corner of  a 10 inch square plate is that one can hear when the cut is nearly through when the lathe tool starts removing metal for the whole revolution of the job. This happily has enabled me to get on with a few other jobs in the workshop while the lathe keeps busy by itself.

The Ford Motor Company can usually be relied upon to come up with some good standards of its own and to adhere to them infallibly. Thus it happens that the position of the gear lever on a Type 9 gearbox is in just the same relative location as that on the Scimitar box; likewise that of the rear mounting.  Even more happily the first motion shaft of the new gearbox is 11.5 mm longer than that of the one belonging to the Scimitar so this is going to be the finsished thickness of the adaptor plate, meaning that the position of the gear lever and rear mounting will be the same amount futher back. This variation is going to be easily accommodated.  The bearing housing on the Type 9 gearbox is smaller than that of the original box which also saves a lot of machining because I can simply produce a one piece plate with a bore which locates on the housing. The plate is being machined with a register of larger diameter which will engage with the Scimitar bellhousing and keep it concentric with the first motion shaft.

My first experience with the type 9 gearbox was during the modifications of a then new XR 4x4i which was being fitted with a turbocharger.  Having fitted the engine and box over the inspection pit I moved the car to a 4 post lift in order to complete assembly and was alarmed to notice how notchy the gear selection felt compared with how the car came in.  The solution was to refit the rubber boot around the gear lever upon which this box apparently relies to give it a nice smooth feel.  I’m hoping to put this experience to good use when designing the gear lever boot fitment on the Scimitar.

More on the conversion is to follow as it all takes shape ready to give the sort of sterling service which it did in the 2.8 Capris which were driven (in a not at all camp way) by Messrs. Bodie and Doyle.

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