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<MISC> Sequential Shifter

With the renewed threads about M3 downshift over-revs, I thought I'd pass on 
some information about a neat piece of equipment I read about.  Last night I was
browsing through the latest issue of Racecar Engineering (very cool, but 
expensive magazine).  They were featuring the workings of standard and 
semi-automatic sequential shift transmissions.  In addition, they had a feature 
piece about a shifting system that can be added to a manual transmission to make
it a sequential shift unit.  The system is made by a French company called 
Selexy and replaces the external shift mechanism.  It can be fitted to either 
synchromesh or dog-clutch transmissions.  One reason race cars use sequential 
shift transmissions is it eliminates mis-shifts, and, therefore, saves time 
around the race course and reduces equipment stress.  The Selexy system can be 
configured for any number of speeds up to 7, with options for reverse and first 
gear lock-out.  There is one caveat when using the system with a syncromesh 
transmission.  Depending on the weight of the synchronizers, the weight of the 
gears, and the time it takes for the transmission to speed up meshing gears, the
speed of the Selexy system may exceed that of the transmission resulting in 
clunky shifts.  I'm not sure if this means that there will be extra or excessive
wear on the transmission, though.  The accompianing pictures showed a very well 
made piece and the article was very positive in its review of the system.

Regards,
Jim Moran
'88 M6