Re: 'Manual' mode of Auto trans

[Brian M Kennedy <kennedy@xxxxxx>]

Derek Ziglar wrote:
> 
> Since at least the late 1980's, BMWs with automatic transmission have
> a pseudo manual mode.
> 
> Does anyone here actually use it?

Judging by the response, no.  (Or maybe people are just afraid to
admit it, because then they'd be labeled as a pansy non-enthusiast
since they have a auto trans. ;^/ )

> Is there anything particularly
> useful I can do with this mode?

Not sure, yet....

> 
> Obviously, nothing beats a *real* manual transmission. But some of us
> who have a significant other who dislikes driving a stick and who
> themselves drive a stick a little too aggressively sometimes have to
> get an auto trans for their own good. But we still wanna have fun!

Well, without operating the throttle and clutch to make quicker and/or smoother
shifts, its not clear to me that manual controlling adds much fun.  Since all you
are doing is choosing when to shift and what to shift into, it would seem to only be
beneficial where the normal auto software does a bad job of choosing.  Given the
pretty good BMW sport mode, the only places I'd expect inferior shifting would be:

	* In aggressive cornering; the software cannot know what
	  the right gear will be when its time to accelerate.
	  It would be nice for it to downshift and lock-up while
	  you are braking, so its ready to go when you are.

	* In full acceleration with JimC engine software; the
	  auto trans software won't let you use the higher rev
	  limits that the JimC software provides.

	* When you are right at the top of a gear, but just 
	  about to brake -- you'd rather just stay at the top
	  of the lower gear.  This is compounded by the inability
	  to use the JimC top of the gear.

The problem, though, with the BMW manual mode is that the controller is fairly
incompatible with the above situations.  In all those situations, trying to make a
delicate one-click shift is tough.  Thus, I suspect few would use it in such
situations.  Its actually easier to left-foot brake and keep the gas on enough to
keep the revs high -- but that of course doesn't work well if you need to threshold
brake.

Luckily, there _is_ a solution:  RaceLogic's SwitchLogic controller gives you a
lever on the steering wheel stalk that you push forward to upshift and pull back to
downshift.  Two pulls means downshift two gears.  And it will wait until it can do
so safely... so, coming into a slow speed corner at 90 mph, you can pull back twice
at the end of the straight, then as you are braking, as soon as it can, it will
downshift and then as soon as it can downshift again.  By the time you are ready to
floor it again, your transmission should be in the right gear, locked-up, and ready
to go.

Now, if you could just get a JimC-aware SwitchLogic controller, you might have
something that a lot more people would use.  Well, except for anybody on this digest
- -- nobody on this digest would be caught dead with an auto trans.  8^O   ;^)


Brian

------------------------------

End of bmw-digest V9 #113
*************************