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Gearbox question, driving style

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  #81  
Old 11-30-2012, 11:17 AM
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Now, is that to lubricate your throat or to celebrate having power fold mirrors?
 
  #82  
Old 11-30-2012, 12:50 PM
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The pf mirrors are controlled via black micro relays on the passenger healboard in rhd cars.

Haven't checked the full thread but I've got some spares.
 
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  #83  
Old 11-30-2012, 12:59 PM
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Originally Posted by plums
Now, is that to lubricate your throat or to celebrate having power fold mirrors?
A bit of both, back home and lubricated now and good for another 6000 miles.
 
  #84  
Old 11-30-2012, 01:10 PM
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Originally Posted by richard thomas
A bit of both, back home and lubricated now and good for another 6000 miles.
You need to shorten the interval for optimal results
 
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Old 11-30-2012, 01:14 PM
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Originally Posted by Sean B
The pf mirrors are controlled via black micro relays on the passenger healboard in rhd cars.

Haven't checked the full thread but I've got some spares.
Yes I noted the relays in the diagram and the footnote for the change in sides when fitted to RHD vehicles.

I was planning on researching whether it was one of those options which only take minor additions to enable. In this case, the two relays. That would be big news for all owners. At least if they had the memory mirrors.

edit:

AHA! Motor is different between non-memory and memory *but* the same between power fold and non-power fold. Sadly, the mirror harness is different, at least by part number. But that may only be a case of the two additional wires.
 

Last edited by plums; 11-30-2012 at 01:25 PM.
  #86  
Old 11-30-2012, 01:30 PM
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Originally Posted by plums
To all three of the above ... the root cause of all fear in snow is learning to drive in the summer in a FWD vehicle. People who learned to drive in the snow with RWD only know that snow is fun time.

Actually, FWD is like a deathtrap in the snow.
Just had to comment having re-read the last page of posts....the most fun i EVER had with a car in the snow was when I owned a Skoda 130 Estelle (5 speed, sunroof, rev counter, electric lights, 40BHP - fully loaded LOL) a while ago - drifted like a baby Porsche, and wasn't worried about being too mental sideways because the car was worth less than the shoes I was wearing!!

Just wish I had kept all of the old Mk 2 RS2000's I have owned....worth a fortune these days! Now they were fun in the snow....

 
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Old 11-30-2012, 01:36 PM
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Originally Posted by plums
Yes I noted the relays in the diagram and the footnote for the change in sides when fitted to RHD vehicles.

I was planning on researching whether it was one of those options which only take minor additions to enable. In this case, the two relays. That would be big news for all owners. At least if they had the memory mirrors.

edit:

AHA! Motor is different between non-memory and memory *but* the same between power fold and non-power fold. Sadly, the mirror harness is different, at least by part number. But that may only be a case of the two additional wires.
What diagram you looking at Plums? Would love a look....

I don't understand what the difference in motor might be for memory and non memory - I thought the motor might be the same but the control module different....I guess we are talking about 2 motors here i.e. the fold motor and the mirror glass motor? In my simple mind the non fold mirrors will not have a fold motor, however memory and non memory should in theory need the same wires to power the mirror glass motor?

It would make sense for the harness to be different for the fold mirrors as the grey and red are there only for the fold motor....all the other wires would be the same for the mirror glass motor, heating and dimming functions?
 
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Old 11-30-2012, 02:48 PM
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I've never had a FWD car-only ever had RWD cars, including a long series of old BMW's that were very entertaining in the snow & heavy rain

In really heavy snow like we had in the UK a few years ago when temps dropped to below -20C, I ended up dropping the tyre pressures from the low 30's to the low 20's to aid grip-it did actually make a difference.

RWD makes you stay awake as it is constant reminder of one's own mortality if liberties are taken when grip is not great-although I love the challenge of driving in snow in a RWD car & it's immense fun to poke the back end out when nobody's looking-just for the hell of it
 
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Old 11-30-2012, 03:17 PM
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RWD is always more fun....very controllable...steer with the throttle....although it is good fun getting lift off oversteer in a Fwd car - I had a 309GTi a while back and it was a hoot!

Edited to say: Just realise this thread was originally about gearbox driving style - diversified a bit from that, sorry Sandy!
 

Last edited by richard thomas; 11-30-2012 at 03:20 PM.
  #90  
Old 11-30-2012, 03:32 PM
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Originally Posted by Red October
I've never had a FWD car-only ever had RWD cars, including a long series of old BMW's that were very entertaining in the snow & heavy rain

In really heavy snow like we had in the UK a few years ago when temps dropped to below -20C, I ended up dropping the tyre pressures from the low 30's to the low 20's to aid grip-it did actually make a difference.

RWD makes you stay awake as it is constant reminder of one's own mortality if liberties are taken when grip is not great-although I love the challenge of driving in snow in a RWD car & it's immense fun to poke the back end out when nobody's looking-just for the hell of it
i would guess that it is better to have them as low as possible contact, not? I always little overinflate tires because smaller contact helps to put pressure on ground ? For the same reason are winter tires recommended to be as thin as possible (i have 205/80 or so).
 
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Old 11-30-2012, 03:40 PM
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Originally Posted by sandy85
i would guess that it is better to have them as low as possible contact, not? I always little overinflate tires because smaller contact helps to put pressure on ground ? For the same reason are winter tires recommended to be as thin as possible (i have 205/80 or so).
Don't believe so - the idea of running lower pressures in bad conditions is to allow the tyre to deform a little and put more rubber on the asphalt. Winter tyres aren't narrower than regular tyres, but they have a different grip compound and more sideways tread-cuts, known in the trade as "sipes".
 
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Old 11-30-2012, 03:49 PM
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It's all about footprint.

Lower the pressures of a 'normal' tyre to get more rubber on the floor.

However it is true that winter tyres can be narrower as the profile, tread pattern and rubber compound are usually designed to suit the conditions....try to imagine an ice skater skating with a plank of wood on each foot and you will get the idea?
 
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Old 11-30-2012, 03:56 PM
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Originally Posted by richard thomas
...try to imagine an ice skater skating with a plank of wood on each foot and you will get the idea?
Ice-skates are supposed to slide!
 
  #94  
Old 11-30-2012, 03:57 PM
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yes but it is contradiction, is it not? Winter tires are supposed to be as thin as possible, so why to make it worse by lowering pressure? I mean you would not get thin winter tire then later deflate it to make it as big footprint as some 305mm would be.
Of course on offroad you want tire to copy the terrain, but in snow you want it to bite and get rubber pressed into micro shards on flat surface of ice?
 
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Old 11-30-2012, 03:59 PM
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Originally Posted by jimgoose
Ice-skates are supposed to slide!
Yes true, but they also bite....
 
  #96  
Old 11-30-2012, 04:00 PM
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Originally Posted by jimgoose
Ice-skates are supposed to slide!
it is not comparable as skates are not rotating. what would bite better, skate 90° turned against moving direction or a ski? If you want to move forward you need as little as possible front resistance and as much as possible pressure on the ice = thin tire with max pressure.
 

Last edited by sandy85; 11-30-2012 at 04:02 PM.
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Old 11-30-2012, 04:02 PM
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Theory is all very well-up to a point, but sometimes you have to try experimenting in the real world. I foudn that on standard tyres, grip was noticeably improved in snowy conditions with lower tyre pressures.

Those were my actual physical observations after driving in snow with tyres at lower pressure
 
  #98  
Old 11-30-2012, 04:06 PM
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Originally Posted by sandy85
...but in snow you want it to bite and get rubber pressed into micro shards on flat surface of ice?
Winter compounds stay soft and "grippy" well below zero. Normal compounds start to harden at around 7 Celsius. The pressing is taken care of by the tread-and-sipe design.
 
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Old 11-30-2012, 04:07 PM
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Originally Posted by sandy85
yes but it is contradiction, is it not? Winter tires are supposed to be as thin as possible, so why to make it worse by lowering pressure? I mean you would not get thin winter tire then later deflate it to make it as big footprint as some 305mm would be.
Of course on offroad you want tire to copy the terrain, but in snow you want it to bite and get rubber pressed into micro shards on flat surface of ice?
You are totally correct - there is no benefit in deflating a winter tyre as the pressure defined for it is it's optimum pressure setting for the conditions...

However, if you were running standard 'summer' tyres in bad winter conditions (snow, deep mud etc.) then there is benefit in lowering the pressures as it enables the tyre to perform better in those conditions.

However I see your logical point that the higher the pressure, the less contact with the road and theoretically the more force the tyre contact surface would have on the road. If all tyres had exactly the same compound and tread pattern then it would be correct to a degree.

However there is a limit - for instance fitting bicycle tyres to the car should theoretically give even more force between the tyre and the road...but there would probably be insufficient grip to move the car at all, the tyre would just spin as there is not enough grip to overcome the inertia of the weight of the car....

Hope this make sense ( please understand that I have been 'lubricated')
 
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Old 11-30-2012, 04:11 PM
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Originally Posted by sandy85
it is not comparable as skates are not rotating. what would bite better, skate 90° turned against moving direction or a ski? If you want to move forward you need as little as possible front resistance and as much as possible pressure on the ice = thin tire with max pressure.
Try to think of every edge of the tread pattern as a 'skate'....they 'bite'

Edited to say: skates are designed to both slide and bite - it depends on the angle with which they are presented to the ice, they can indeed slide but when angled bite instead.
 

Last edited by richard thomas; 11-30-2012 at 04:20 PM.


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