Synchro wear and double clutching

[C M Smith <cmsmith@domain.elided>]

Imagine how long first gear synchro lasted if you upshifted at redline, i e 
revved the engine to redline then selected first gear (even with the clutch 
disengaged!) or downshifted from second without double clutching. Second 
gear works hardest only because first gear isn't abused in this way. Second 
gear is a big piece of steel and spins quickly when you are in the upper 
gears. Definitely double clutch if you are skip shifting down the box, and 
I do it anyway without a thought now I've been driving manual boxes for 30 
years. It isn't just Alfa's that don't appreciate being speedshifted at 
redline or downshifted with no attempt to match gear speeds.

A double clutch downshift to second gear is very beneficial, provided you 
do in fact match the gear speeds. Over revving a double clutch shift is 
worse than just letting the synchro do the work.

I have found most cars benefit enormously from a double clutch downshift 
into first gear. In fact, many boxes will baulk badly unless you at least 
try to match gear speeds on the downshift by double clutching. Having said 
that I always found it ironic that the second gear synchro supposedly so 
weak in Alfa gearboxes could handle a non double clutched downshift into 
second but would crunch on the way up the box!

Heel and toe is only necessary to achieve this if you are diving into a 
corner under trail braking, but once the habit is developed it is hard to 
break (as well as pointless to break such a beneficial habit, if you double 
clutch you might just as well heel and toe, if you also need to brake as 
you approach the corner) Older Alfa's are awful to heel and toe. Starting 
with the Alfetta series they became much easier. the best was the GTV6 
IMHO, though my 164 is fairly easy to do, the brake and gas are too far 
apart and the brake pedal a bit high. I blame that on three factors. First, 
the dreaded Audi unintentional acceleration fiasco seems to have influenced 
ergonomic guys into separating the brake and gas pedals by more distance 
than is useful, second we rarely get deep into the brakes on the street, 
which is when the brake pedal gets down to where the gas pedal is normally 
and after all you should really be hard on the brakes if you feel the 
absolute need to heel and toe, and our need for relaxed highway cruising in 
North America means the ideal height for the gas pedal for spirited driving 
is quite a bit higher than for cruising at 70 mph in a powerful modern car. 
I recall the best way to drive a Lancia Beta fast was with hands at 8 and 4 
on the wheel and both feet off the floor!!!

Cheers

Michael



Michael Smith
Calgary, Alberta,Canada
91 Alfa 164L
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