another question about cruise control

On Tue, 12 Jun 2012 10:54:54 +0100, "Tim Downie"


I'm struggling to think of an occasion when I would want to change
down a gear with cruise engaged. If preparing to slow down I wouldn't
be changing gear anyway and if preparing to speed up I'd probably just
use multiple +5mph clicks on the cruise stalk. If preparing for a more
aggressive move, I'd disable the cruise using the stalk first.

--
Z

My auto BMW will change down on a steep hill to maintain the set speed.
But it does have a very tall top gear.

--
*Organized Crime Is Alive And Well; It's Called Auto Insurance. *

    Dave Plowman        dave@davenoise.co.uk           London SW
                  To e-mail, change noise into sound.

On Mon, 25 Jun 2012 11:18:27 +0100, "Dave Plowman (News)"


Ooops. I'd forgotten about that. Spoilt by the torque in my 3 litre
diesel BMW, it's not something I've ever had to do.

I'm also forgetting about  switching on headlights, wipers and, to a
significant extent even, the engine. I know I'm unusual for even
having a manual box in these lazy days..

--
Z

On 25/06/2012 12:04, Zathras wrote:

On the six cylinder BMW diesels of the era of yours, you have cruise
control with brake function.
Going down a steep hill with cruise enabled, the car will 'brake' itself
if the speed increases an amount above the set point. How much above the
set point the speed has reaches before the car brakes, I'm not sure as I
cannot see the brake lights come on from the driver's seat....

David

Same here. It feels as though it brakes quite a lot for me though.
When the economy meter end-stops and there is more braking effect
after that point makes me think it's actually braking. I believe the
car has quite a tight control of over-speed but I've never really
tested it personally.

--
Z

On 28/06/2012 13:33, Zathras wrote:

I have a 118i auto (until tomorrow), and a 335d auto, both of which are
(sept) 2009 models with "Efficient Dynamics".

On the smaller petrol engine car, I can feel the "brake energy
regeneration" (BMW marketing speak, internally known as "Intelligent
Alternator Control" which is a far more accurate title) and see the
battery charging voltage rise over a period of one or two seconds on
over-run, it doesn't suddenly turn on the alternator. Whereas on the
335d, I cannot be sure that it is the increase of the charging voltage
of the battery on over-run.

It is difficult to separate whether it is the brake function of the CC,
or the increase in battery charging that causes deceleration back to the
set point.
For instance, when running with CC, and coming up to a slower vehicle,
to overtake the accelerator is pressed for a few seconds and then after
passing the vehicle, the accelerator pedal is released and I often
wonder if the car is braking back to the set point, or the alternator is
charging the battery until the original set point is reached.

David

It would probably benefit from a taller top gear if it will climb any hill
in that gear.

--
*Pentium wise, pen and paper foolish *

    Dave Plowman        dave@davenoise.co.uk           London SW
                  To e-mail, change noise into sound.

On Mon, 25 Jun 2012 13:28:43 +0100, "Dave Plowman (News)"


Not sure..it's got 6 gears and does about 2000 rpm at speeds plod
would become genuinely interested in on the motorway. The real trick
is the 295 lbft at 1300 rpm. Being an early "efficient dynamics" car,
I can get anywhere from typically low forties to mid fifties out the
thing - it's by no means a heavy drinker as it is. Never having to
change down on the motorway is quite relaxing really.

I'm so pleased with the motor that I'm not buying another 3 unless the
6 cylinder diesel is fitted.

--
Z