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Engine braking & downshifting



OK.  I've sat by and watched this thread come and go.  Now, please bear with
me as I add my 2 cents.  While the experts agree that engine/compression
braking does not add any real benefit to the driving experience (yes, that's
why we have brakes --- and good ones on our Bimmers), there is still the issue
of appropriate downshifting, which may cause a certain amount of compression
braking in itself.  

In the situation described above, assume that we are cruising along a main
street at approximately 40 MPH in 4th gear.  Up ahead we see a red light, the
choice? 1) Simply apply brakes and let clutch in when we are close to a stop.
2) Brake, downshift to third, preferably via heel & toe technique to match
engine revs, continue braking, possible downshift to second, brake & slow to a
stop.  Either example will stop the car at the red light.  #1 is a lot easier.
 #2 requires some extra effort.  The only advantage to #2 is that if the light
happens to change to green as you are slowing down, you will now likely be in
a better gear to resume speed, or to accelerate back up to your previous
cruising speed.  This is how I like to drive at all times, to be in the
appropriate gear for the speed I am travelling.  

In example #1, you are slowing down in 4th gear and the light changes to
green.  This means you will either a) be in fourth gear at low RPM's where
accelerating will be painful, or you will need to quickly find the appropriate
gear (3rd or 2nd), or b), you will have already let in the clutch and may be
slowing down in neutral. Again, you will need to quickly find an appropriate
gear, tough to do when you are cruising in neutral, where a quick choice could
find you in 2nd instead of 4th and I don't want to get the over-revving engine
thread started again, so I'll leave it at that!

John
'99 ///M Roadster
'95 325i
BMWCCA
BMWCCC

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End of bmw-digest V9 #1024
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