That sound like good advice, Avant.
Personally, I've never experienced the manoeuvring problems with automatics that other people mention. Surely, if you have a 'proper' automatic, as soon as your foot is off the footbrake it creeps - at a perfectly adequate pace for manoeuvring - so you don't need to touch the throttle, just cover the brake?
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I don't get two-footed auto driving, either.
The little pedal is 'go', the big one is 'stop'.
Why would you want to stop and go at the same time?
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>>as soon as your foot is off the footbrake it creeps - at a perfectly adequate pace for manoeuvring -
Ever tried on a hill? Or with a heavy trailer? Or at the edge of a speed bump - you need the power to cross the bump, but the moment you're over it you need to stop. Or even jst with the sort of big heavy car that attracts an auto box.
>>Why would you want to stop and go at the same time
You don't. But you might want to stop, and then go, and then stop again. As in the above examples. By the time you've wound up the torque converter enough to get the vehicle to move, you've got a load of power behind you that doesn't go away that quickly.
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Yes creep only works on the flat and shallow slopes. Whilst on the move, I'm in favour of using the right foot only but in towing situations, steep hill starts, parking on slopes etc I'll left foot brake to get the torque convertor to bite. It (the torque converter) wont creep you if you are on too steep a slope and you'll roll back hence the need to accelerate and brake at the same time untill you feel the car wanting to go.
Yes, you can use the handbrake if you like, but it tends to grab a little so the footbrake just smooths things out. You wouldnt really want to use the handbrake if you were rolling forward or back anyway.
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Mine (Merc C270CDi) doesn't creep even on my apparently flat drive. In the space I park in, it needs the front to go as close to a wall as possible, and I always have my heart in my mouth if I've left car a little short and have to move it up a touch!
There's no real lag on take-off with my car, but I've driven other diesel autos (worst was Mondeo TCDi auto from a bout 4yrs ago) where take off lag was horrendous. It was useful to be able to swap feet on the brake pedal and spool the engine up. The the turbo would cut-in and I was very glad it was an auto as you needed both hands to hang on to the steering wheel with!!
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>>Yes, you can use the handbrake if you like,
To stop a moving car? You're not on the list of people allowed to borrow mine.... ;)
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I drove a Citroen C2 recently with one of those new-fangled automagical gearboxes with no torque convertor, but a computer-controlled clutch instead. It was a pig to drive, you had to rev the engine to make it move and parking was a nightmare. One foot on the brake, rev the engine until you feel the computer put the clutch in, release the brake, shoot backwards, stamp on the brake, repeat.
It was rubbish.
Edited by David Horn on 02/09/2008 at 19:19
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So if the brake pedal is bigger simply because there is the space to make it bigger, why not have a gigantic accelerator pedal aswell, to enable swifter progress?
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Autos were developed in America where the cars were big and heavy. Traditional autos in D have little or no engine braking, so car buyers obviously wanted a reassuringly huge AAARGH STOP! pedal. Vacuum-assisted brakes were also first mass-produced in America, and given the power (when not overheated) of drum brakes, and the need for small women to drive vast cars, the merest touch on the pedal could lock all the wheels and make marks on the road. A small pedal would have been more sensible really.
:o}
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Other side of the above coin.....
..... automatics were common in the USA before servo brakes, but the cars were big , heavy and had powerful big-cube motors too. Is it not possible that the big pedal was to facilitate drivers using BOTH feet to achieve an emergency stop in those circumstances; there being of course LESS engine braking with an auto.
Only a guess mind.
One minor item that I'm surprised no-one's commented on, as far as I can see. The old Mini had a "normal" brake pedal in automatic form; it was also unusual for its time in being a 4-speed automatic.
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The AP transmission used in the Mini and 1100 wasn't a normal slush-pump system, although I don't know how it worked. I seem to remember stories of unreliability, and the gearchanges tended to be jerky. Never drove one for long enough to learn it properly, and perhaps it couldn't be learned. I believe it was more economical than conventional autos.
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>>The AP transmission used in the Mini and 1100 wasn't a normal slush-pump system
It was fairly normal, except that instead of forming the epicyclic gear train using spur gear and straight cut internal gears, the AP automatic used bevel gears - similar in concept to those in a differential.
On some early versions, there was a secondary pump, driven by the output shaft, and so, these automatics could be bump started.
They seldom lasted long!
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Ref N.C.'s comment re auto Minis, I had one for several years. The bump-start capability came in handy a couple of times, and it did tend to get through free-end engine mounts, but otherwise very reliable. Easy to 2-foot drive too, and necessary in N.Z. traffic where turn signals are used to inform you that you have just been cut up, not that " I wish to pull in front of you". The few milliseconds saved were helpful. In heavy traffic, I didn't ride the brake, but kept my left hoof very close by.
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>>>where turn signals are used to inform you that you have just been cut up,<<<
Ah ... I've always wondered where all the London bus drivers retire to!
Dog : )
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My Almera 1.8 has got quite good engine breaking Lud, which is just as well really being I live in Cornwall, I switch off the overdrive - which is essentially the 4th gear, when decending a hill, and I'll even nudge it into 2nd sometimes for the breaking effect ... but I'll tell ya what, break pads & disk replacement costs a whole lot less than a new gearbox, or the clutch replacement on a manual.
Ladydog does none of this - she just drives the darn thing !
Dog.
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No, as from my post.
>>You wouldnt really want to use the handbrake if you were rolling forward or back anyway.
BTW what sort of car would I be missing out on? ;-)
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Ever tried on a hill? Or with a heavy trailer? Or at the edge of a speed bump - you need the power to cross the bump but the moment you're over it you need to stop. Or even jst with the sort of big heavy car that attracts an auto box.
In these situations I used to use the choke to raise the revs and just hover over the brake pedal with my right foot, not possible on modern cars. Only works upto a point, then of course it chokes the engine completly.
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No automatic car I have ever owned - mostly Hondas but Rover and Daimler as well, to name a couple - have ever run back on hills and they've always crept on tickover.
Every day I used to manoeuvre my 16ft Legend Coupe into a space surrounded by three low brick walls with just 18in clearance front and back. This was a car with long front and rear overhangs, too. Passers-by used to stand and watch, then ask how it could be done with such a big car...it was simply because I only ever needed one foot to cover the brake. If I was clever enough I could post a pic somewhere of the car standing in its niche, if anyone does't believe me.
I've never driven with a heavy trailer but I have been told proper autoboxes are not the answer for that sort of work as they need extra cooling, etc.
I'm no technician either, but it seems to me that if the torque converter is doing its job it should be allowing the vehicle to move slightly, even at tickover if required, while not allowing it to stall.
I don't buy this 'brakes are cheaper than gearboxes' argument either. My car handbook tells me to use the transmission for engine braking. I should think people who fall for the ridiculous 'new discs and pads needed guv' line every 12,000 miles will have spent the price of a gearbox after a few years anyway.
Maybe I've been lucky enough (up to now) to avoid compromised engineering.
Edited by mike hannon on 03/09/2008 at 12:57
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