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downshifting after exiting motorway watch

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    (Original post by tface)
    ...
    Hi, I did say that I'd post the link to another defensive driving website when I found it, here it is:

    http://www.smartdriving.co.uk/Driving/index.htm

    Matt
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    (Original post by gbduo)
    Heel and toe sequentially down through the gears. Anticipate long in advance, use engine braking down to a sensible speed and then brake to a stop.

    If you time it properly, you will be just about to hit the foot brake when the traffic lights change and you can pull away in the correct gear because you have been shifting correctly.

    The thing about causing damage to your gearbox and clutch is utter BS if you can heel and toe (and go down a gear box sequentially).

    PS I guess I should say, don't try to heel and toe in a car that has pedals which are staggered. It won't work. But if you are just changing down and using engine braking, you can blip the throttle with your right foot as normal with your left foot on the clutch and rev match.
    Yeah this. Hell and toe is horrible in my car but you can still eliminate any significant clutch wear (which tbh is minimal anyway) by doing a bit of rev matching when down changing.
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    (Original post by J_90)
    I change down gears and use engine braking, a concept that 98% of people don't understand.
    do you drive a particularly heavy/ underbraked LGV/PCV without a retarder or a vintage vehicle ?

    if not 'active' engine braking and changing down are not the recommended techniques .... vs 'acceleration sense' and specific conditions where you would 'hold' a gear (e.g. alpine pass or somesuch )

    IPSGA anyone ....

    and as Walter pointed out Push-pull is not 'shuffling' ... i think you are confusing the 'learner shuffle' / pull -pause-pull with push-pull ....

    fixed / rotational input only works on go-karts and racers with stupidly 'fast' racks / narrow lock ...
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    (Original post by J_90)
    I have been mentored by some ex pro racing drivers and I copy the way they drive and it's much better for me personally and they agree with it, who am I to argue.
    i don't know how about nearly every organisation acknowledged to be expert in ROAD driving ... and not just the I Am Meldrews ...
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    (Original post by Butane)
    If pedal spacing allows it (i.e. accelerator and brake aren't practically on opposite sides of the bloody footwell), heel and toe down through the box. Otherwise, just downshifting and revmatching until I get close to the end of the sliproad (or traffic in front) and have to brake.
    or you could stop treating it like GTA and follow the orthodoxy of Advanced driving which sees the use of acceleration sense and then braking until you actually need to down shift - then block changing depending on the picture that has developed as you slowed ...
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    (Original post by ily_em)
    Why is nobody taught to do this in driving lessons? I assumed it was bad; everybody I know is just taught to slow with the brakes...
    because as a technique outside a few niche settings it's 50 + years out of date ...

    as for those wanting driver training and development

    there's the RoSPA RoADAR groups http://www.roadar.org/

    or the I Am Meldrew lot http://www.iam.org.uk/
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    What a weird question, its the same as any other junction you approach. Filter off, take foot off the gas, let the car roll to the junction (this uses no petrol at all on newer cars) brake when you are near the junction, put into second and accelerate if its clear.
    Simples
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    (Original post by Butane)
    What did you do to control your speed when descending a steep incline? Ride the brakes?
    this is what the number positions on a auto are for by limiting the box from changing above that gear - giving some engine braking effort
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    lol, why is there a thread about this?
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    Riding the brakes is the way forward apparently....
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    (Original post by J_90)
    Riding the brakes is the way forward apparently....
    Cars don't need brakes apparently....
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    (Original post by J_90)
    Riding the brakes is the way forward apparently....

    you are either a troll or a phenomenally poor driver ....

    same goes for Astra_K as well
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    Heel-and-toe, like a boss.
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    (Original post by iwantcheese5)
    70 in second is do able in my car :P
    'fraid not. Cars nowadays are "designed" to get to 62mph (100kmph) in second. Why this is I don't know....
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    (Original post by JamesyB)
    'fraid not. Cars nowadays are "designed" to get to 62mph (100kmph) in second. Why this is I don't know....
    For the RX-8's second gear top speed:

    (0.00595) * (RPM * r) / (R1 * R2) = vehicle speed in miles/hour

    where:
    RPM = engine speed, in revolutions/minute
    r = loaded tire radius (wheel center to pavement), in inches
    R1 = transmission gear ratio
    R2 = rear axle ratio
    0.00595 = conversion from inches per minute to miles per hour

    RPM = 9000
    r = 12.985"
    R1 = 2.269
    R2 = 4.300

    This gives you a speed of 71.3mph
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    (Original post by iwantcheese5)
    For the RX-8's second gear top speed:

    (0.00595) * (RPM * r) / (R1 * R2) = vehicle speed in miles/hour

    where:
    RPM = engine speed, in revolutions/minute
    r = loaded tire radius (wheel center to pavement), in inches
    R1 = transmission gear ratio
    R2 = rear axle ratio
    0.00595 = conversion from inches per minute to miles per hour

    RPM = 9000
    r = 12.985"
    R1 = 2.269
    R2 = 4.300

    This gives you a speed of 71.3mph
    Exception that proves the rule plus that's a rotary engine :P
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    (Original post by JamesyB)
    Exception that proves the rule plus that's a rotary engine :P
    I would bother to do it for the 300ZX as well but you'd probably say that it was too old to count. Also my housemate owns a Mark IV Golf V6 4Motion which can't even do 62mph in second. The same is also true of the R32 golf which can only reach 55mph in second due to the very short ratios it uses.

    Seriously it's different in every car because of the gear ratios, wheel diameters and maximum rpms...
 
 
 
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