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The Natural Philosopher[_2_] The Natural Philosopher[_2_] is offline
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Default OT: Manual or automatic gearbox? and XC60 opinion...

On 08/06/2021 20:45, NY wrote:
Yes I think we are all agreed that because automatics only have an
accelerator and a brake to regulate speed, whereas manuals also have a
clutch that can be slipped, *low-speed* *precise* movement is more
easily achieved with left-foot braking in an automatic.

Good. That is one HUGE advantage of it.

But is there any
advantage in using the left foot to brake in normal driving? Or is it
just a case of doing it because you can, rather than for any better
reason. I have no problem using the same foot for brake and accelerator
in a manual, so I don't see the benefit of using different feet in an
automatic. Maybe there's something explanation that I'm missing...

Well lets say that you can speed up reactions by maybe a couple of
hundred milliseconds, if your left foot is poised over the brake.
And it *used* to be a very good way to manually (pedally? ) control the
auto box - police drivers back in the day were taught to use it to get
best performance (and destroy the brakes) of their auto cars

These days with complex software, flappy paddles and different gearbox
modes, it's less of an issue

OK, so rally drivers resort to heel-and-toe operating the brake and
accelerator at the same time, but I'm thinking of normal driving where
you brake before the hazard and then accelerate out of it, and so don't
need to operate both pedals simultaneously.

They do that - or did that - to speed up the gear change especially with
straight cut non synchro boxes. These days gear changes are automatic.

I remember the lap record of all time being broken in a Williams Turbo
car by keke rosberg. I was there watching him *coast*, with the clutch
down, round Club Corner at about 140mph, blipping the throttle to keep
the turbos spun up before dropping the clutch and mashing the go pedal.

People who learnt ways to keep boost up - Senna was another - did well
in that era.

Given that every automatic I've ever seen, going back to the mid sixties
(*), has an extra-wide footbrake pedal, the concept of left-foot braking
is something that has been around for a long time with automatics. So in
the early days of automatics, someone perceived that there was a benefit
of allowing it. I'm trying to work out what that reason was and still is.

You should ask yourself why anyone thought it was a good ideas to have
three pedals when you only have two feet.

Left foot braking is becoming - apart for precision parking - far less a
necessity and far more proscribed by software in modern cars.
Back in the late 80s when I got my first auto, it was very useful. Now
its a pain because the software detects it and sulks

A lie can travel halfway around the world while the truth is putting on
its shoes.