This has been mentioned recently in Mini Magazine and RetroCars mag. For those who are considering going the programmable ignition route but still want to retain the classic distributor -
http://www.aldonamethyst.co.uk/
Quote:
Aldon automotive has developed a new distributor with fully-programmable ignition curves, called 'amethyst'. The rebuilt lucas distributor is modified to connect up to the supplied microprocessor control unit, which can be hooked up via USB to a PC laptop. The ignition advance curve can then be modified to suit the engine using the included software. The set-up is a decent half-way point for those wanting the performance benefits of mappable ignition but without the costs of a distributorless system. It will be available from mid-September, and Aldon will even be able to map your ignition advance for you from their West Midlands base
Don't think it is out yet but takes vacuum and a feed from the dizzy. 10 storable curves and can switch between 2 in car without computer. Never going to be quite as accurate as a crank sensor but a lot easier to fit. And not the same as the 123 dizzys - the Aldon amethyst is fully re mappable .
Personally I think I'll stick with the custom Scorcher with no vac advance mechanism.