> Top on that,
> engine braking is more economical than using the brakes.

Depends how expensive it is to replace the clutch :-)

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scott wrote:
> 
> It's funny when my car does this, if you leave all the ESP stuff turned
> on and then try to fishtail the car after approx 0.1 seconds of sliding
> you can feel it pull on the brake on just one wheel that gets the car
> back in shape.

Ahh, Audi takes more time, it lets the slide start but then crunches the
car back to line.

BMW?

> My changing-down-on-ice experiments were exactly to see if the ESP
> system could cope with it, but alas it couldn't and I just slid with a
> wiggly back end until it gripped again.  I guess the ESP programmers
> didn't include a function to blip the throttle if it detected engine
> braking was locking the rear wheels :-)

I don't even need to brake with the engine - if I have too much speed
for a corner, keep the throttle steady and turn quickly, car goes
straight ahead and ESP does nothing.

-Aero

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scott wrote:
>> Top on that,
>> engine braking is more economical than using the brakes.
> 
> Depends how expensive it is to replace the clutch :-)
> 

Ummm.. no, bad clutch-usage ain't dependent on engine braking. :-)

-Aero

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On Fri, 13 Feb 2009 13:53:30 +0200, Eero Ahonen wrote:

> Jim Henderson wrote:
>> 
>> Um, no, the brakes don't do the same - if you have disc brakes, the
>> brakes stop the wheels when fully engaged (I don't have drum brakes so
>> I can't comment on those).
> 
> Yes, also on drum brakes. But why on earth would you engage brakes
> fully, if you're not trying to stop the car as quickly as possible?

Because slamming on the brakes on ice doesn't have that effect.

>> Conversely, by downshifting, you increase the engine revs and the
>> wheels are not locked - they still turn.
> 
> Yes, if you'll do it carefully enough (see the similarity to brakes?)
> :). It's possibly a bit easier to be carefully enough, since the maximum
> braking power is very limited.

Yes, but that's the reason to do that.  Similarly, for going down steep 
inclines, using the engine to slow the vehicle down rather than the 
brakes keeps you from burning the brakes out.

> And yes, I actually managed to found one +point to engine braking - with
> FWD car it practically ever won't spin the car, since rear wheels won't
> lock.

Yep, that's another big advantage.

>> Now, when you're on dry pavement, the wheels normally don't lock
>> because the car's momentum overcomes the friction on the brakes,
>> bringing you to a gentle (or sometimes less-than-gentle) stop.
> 
> Either you're having really bad brakes (repair them!) or you're not
> anymore engaging them fully, when driving on dry pavement (so why to do
> it on ice?).

I don't do it on ice.  You can (and I can) lock the wheels driving at 50 
MPH with the brakes, but that also is likely to cause an uncontrollable 
skid - though a shorter one - and often that is more desirable than 
running into whatever it is that you're braking hard to avoid.

>> On ice, though, it takes
>> less friction of the brake pads against the wheel to stop the wheels
>> because it takes less to overcome the friction of the wheel against the
>> ground.
> 
> Yes, the scale is smaller, but it's still there.

Sure, I wouldn't disagree with that.

Jim

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On Fri, 13 Feb 2009 14:01:18 +0200, Eero Ahonen wrote:

> Jim Henderson wrote:
>> 
>> I wouldn't do 4th to 2nd.  Always one gear at a time, otherwise as you
>> state, you can cause the wheels to lock up.
> 
> I do that (downshifting 2-3 gears at once) every day while slowing down
> from the motorway - either 6-5-3-2, 6-4-2 or 6-3-2, depending on place,
> traffic etc.

Ah, I've never driven a 6-speed vehicle.  From higher gears it would 
probably be less of an issue, but dropping from 3 to 1 can redline the 
engine, at least IME.

> And I've managed to lock driving wheels up even without downshifting, by
> just lifting the gas pedal (icy, Volvo 740 and Nokian HKPL4 (studded and
> very good winter tires)). Pressing clutch to get traction back and using
> brakes (=braking with front wheels) were the savior of that situation.

Yes, effective use of the clutch in that type of situation would also 
help - since it would engage/disengage the engine from the drivetrain.

> But yes, usually with FWD car it's pretty hard to mess up with engine
> braking, we certainly agree on that.

:-)

Jim

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scott wrote:
> braking was locking the rear wheels :-)

Funky enough, the cruise control on my Camry will downshift the transmission 
going downhill to keep the speed in range.

-- 
   Darren New, San Diego CA, USA (PST)
   "Ouch ouch ouch!"
   "What's wrong? Noodles too hot?"
   "No, I have Chopstick Tunnel Syndrome."

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On Fri, 13 Feb 2009 08:24:33 +0000, Stephen wrote:

>>>>LOL, arguably, the question comes up if a dyslexic person wouldn't in
>>>>fact describe themselves as "lysdexic"....?
>>>>
>>> No.
>>
>>Well, I was making a joke - if it touched too close to home, please
>>accept my most sincere apologies.
>>
> No you didn't, I'm long past caring what people think 'cause I can't
> spell or read big books. :)

Good man. :-)  I didn't think I'd caused offense, but with a one-word 
answer it's hard to tell.

> I do get pissed off with people who don't take the trouble to check
> their spelling especially when they know they can't spell. I even use
> "Word" when I'm writing a hand written note or letter. But then I'm from
> a generation where it was considered important U no wat I meen?

Same here, though I don't often write anything by hand anymore.  I need 
to have a doctor check out my hand (mentioned a few months ago up here) 
because I get really bad cramps if I use a pen too long.  Signing my name 
and dating a document are about the extent of what I write any more with 
a pen.

>>I could see that.  I often will spell something the way I think it's
>>spelt and it doesn't look right.  In my newsreader, of course, it
>>doesn't look right because of the squiggly red line underneath the word.
>>
> I've switched that feature off in my newsreader. It would drive me mad
> seeing other posts :lol:

Ah, see, in my newsreader, it's only on in the message composition 
window. :-)

>>I occasionally get grief from people about it, or light joking about it.
>>One of my coworkers noticed it a few years ago and asked me about it -
>>not because he was anything other than curious, though - his background
>>is linguistics.
>>
>>I don't know why I started using Queen's English spellings, though -
>>just became a habit.  Possibly because I spent a lot of my time writing
>>to brits. :-)
>>
> If you can't beet them, join them ;)

LOL.  Yeah, I guess that might be part of it.

> Did you know that the term "Brit" used to be offensive? It was used by
> the Irish republicans during the troubles and was not complimentary ;)
> Nowadays the word is in favour.

I didn't know that - thanks!  Another day with something learned, another 
day not wasted. :-)

Jim

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On Fri, 13 Feb 2009 14:05:39 +0200, Eero Ahonen wrote:

> And if you'd had ESP, it should've braked for you (with just left
> wheels, to make the car turn) . For some reason (dunno why) Audi's
> (tested with B7 and B8 A4's) don't seem to do this - if you turn the
> wheels too quickly on ice and slide forwards without turning, the ESP
> won't realize it and does nothing.

LOL, now there's something that would be fun - a car that is driven 
through a neural interface.

Jim

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On 13 Feb 2009 13:04:40 -0500, Jim Henderson <nos### [at] nospamcom> wrote:

>Good man. :-)  I didn't think I'd caused offense, but with a one-word 
>answer it's hard to tell.
>

True ;)

>> I do get pissed off with people who don't take the trouble to check
>> their spelling especially when they know they can't spell. I even use
>> "Word" when I'm writing a hand written note or letter. But then I'm from
>> a generation where it was considered important U no wat I meen?
>
>Same here, though I don't often write anything by hand anymore.  I need 
>to have a doctor check out my hand (mentioned a few months ago up here) 
>because I get really bad cramps if I use a pen too long.  Signing my name 
>and dating a document are about the extent of what I write any more with 
>a pen.
>

I use a pencil and pad if I'm taking notes in meetings or at home. It changes
the tendons I use and keeps RSI away.


>> I've switched that feature off in my newsreader. It would drive me mad
>> seeing other posts :lol:
>
>Ah, see, in my newsreader, it's only on in the message composition 
>window. :-)
>

It might be the same in mine but I'm a habit of creature, whatever :)

>> Did you know that the term "Brit" used to be offensive? It was used by
>> the Irish republicans during the troubles and was not complimentary ;)
>> Nowadays the word is in favour.
>
>I didn't know that - thanks!  Another day with something learned, another 
>day not wasted. :-)
>

We are here to serve :)
 
-- 

Regards
     Stephen

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On Fri, 13 Feb 2009 21:12:23 +0000, Stephen wrote:

> On 13 Feb 2009 13:04:40 -0500, Jim Henderson <nos### [at] nospamcom> wrote:
> 
>>Good man. :-)  I didn't think I'd caused offense, but with a one-word
>>answer it's hard to tell.
>>
> True ;)

Far easier with the smiley. ;-)

>>Same here, though I don't often write anything by hand anymore.  I need
>>to have a doctor check out my hand (mentioned a few months ago up here)
>>because I get really bad cramps if I use a pen too long.  Signing my
>>name and dating a document are about the extent of what I write any more
>>with a pen.
>>
> I use a pencil and pad if I'm taking notes in meetings or at home. It
> changes the tendons I use and keeps RSI away.

I wonder if mine is some sort of RSI; I type a *lot*, and I type quite 
fast as well (I've been clocked at 90-120 WPM when I'm "in a groove") - 
my coworkers are still surprised at how quickly I can type.

Comes from back in my days programming - in my head, I'd be a few lines 
ahead of where my fingers were typing and my speed increased in order to 
keep up with my brain.  Strangely, though, I don't do so well if I have 
to type numbers with text.  I can do 10-key very quickly as well, but 
mixing alpha and numeric slows me down considerably.

>>> I've switched that feature off in my newsreader. It would drive me mad
>>> seeing other posts :lol:
>>
>>Ah, see, in my newsreader, it's only on in the message composition
>>window. :-)
>>
> It might be the same in mine but I'm a habit of creature, whatever :)

LOL

>>> Did you know that the term "Brit" used to be offensive? It was used by
>>> the Irish republicans during the troubles and was not complimentary ;)
>>> Nowadays the word is in favour.
>>
>>I didn't know that - thanks!  Another day with something learned,
>>another day not wasted. :-)
>>
> We are here to serve :)

I'll take a two-piece fish & chips meal, then, served in the traditional 
way. ;-)

Jim

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