CLASSIC DRIVE
We discover the startling transformation which can be gained from applying modern gearbox technology to older Jaguars.
I DROVE AN Austin Seven the other day - one of my all-time favourite classics and of course the car which also got Jaguar started in the car-building game. With just three non-synchro gears and a feeble 17bhp from the 747cc engine it still manages to put a smile on your face, yet it also illustrates perfectly how far the science of automotive engineering has come. These days an engine of that size would be turbocharged and festooned with electronics to the point where it wouldn't be far off the power output of an X-TYPE from just 20 years ago.
One thing which often gets overlooked though is that the march of progress and the quest for green credentials has seen the science of transmission design advancing just as far as engine design.
It's the clever automated manuals which get the headlines, especially the twin-clutch DSG-type boxes, but what's often overlooked is that the traditional torque converter automatic hasn't gone away and in fact has quietly evolved to the point where it's unrecognisable as a descendant of the jerky old Borg Warner and Hydramatic units fitted to older Jaguars.
With the theme of this issue of JW being modified Jaguars, naturally we've tended to concentrate on the engine tuning side of things, a science notorious for dwindling returns as cost increases. What, though if you were able to replace the antique automatic gearbox technology with something more modern and make more efficient use of the power you already have?
Someone who has already been through that exact thought process is Andrew Parkinson at Kent-based Jaguar specialist Motor Legends. It started when company proprietor Keith Perkins returned from a trip to New Zealand, bringing with him a barn-find Series 3 E-type. The car was restored to original specification since Keith wanted the convenience of the self-shifter yet it wasn't long before he found himself feeling the old three-speed Borg Warner Type Model 12 gearbox really rather stifled the V12's performance.
Andrew was duly challenged with the task of researching a more modern automatic which could serve as a replacement, but this wasn't the simple tape-measure-and-welder task you might think. For one thing, the gearbox had to physically fit the available space but more crucially, the majority of modern computer-controlled automatics are designed to work in conjunction with the engine management electronics of the car they were originally installed in. When removed from their original home, there's simply no way of accessing the control electronics and naturally the OEM gearbox makers aren't keen on helping out.
However, it was during a trip to the gigantic SEMA aftermarket tuning show in Las Vegas that a plan came together when the Motor
