rec.autos.simulators

The feasibility of omitting gears may to an extent have also been
speed-related. Going from 4th to 1st like Leo says may have worked at low-
to low mid-range velocities for the target gear.

But I'll readily admit that this is all so long ago and dim in my memory
that I'm not so sure of any of the above <g>

Achim

Mark

Mark

Jonny

Not entirely sure of the reason for sequential shift mechanisms,
but they simplify the actuation requirements for a semi-auto and
(with early mechanical versions) eliminate the risk of the driver
picking 2nd instead of 4th and breaking something... though the
electronics have now taken over that function.

Jonny

I've been trying to find the Top Gear episode where the test drive
were featured on the net, but no such luck. Found a bunch of others
but not that one. I remember watching it on BBC World in '97 or '98,
would be great to watch it again.

I always use all the gears in the box when changing down in real life,
and it is definitely quicker to slow down than just hitting the lowest
gear at the end of the braking zone. I suppose GPL would be the same.
The major problem is that you can exceed the limits of the driven
wheels a lot quicker when using engine braking, and I have had my
rears lock up occasionally if I get the timing wrong (you can imagine
what happens next!). It is especially a problem in the wet, where just
changing from 5 to 2 is usually a lot safer.

Interestingly enough, new drivers are taught in their driving tests to
slow to the speed they require, THEN change to a suitable gear. Maybe
that is so new drivers don't have to use the clutch too much and
possibly become better at controlling a car. Of course lowering speed
limits and making flashing lights by the roadside is a lot better than
actually teaching people to drive properly. Just ask the government.
You are obviously going to be safer if you spend most of the time
looking for speed cameras, watching your speedo and being distracted
by big signs flashing at you when you pass, rather than actually
concentrating on driving safely. Damn British government. We should
rebel....

It also means far less wear on the clutch and synchros, which are a
*little* bit more expensive to replace than brake pads ;-)

Disagree that making a single downshift is not driving 'properly'.
The usual racing motto is "gears are for going, brakes are for slowing"
(with the obvious road driving exception of long downgrades).

I'm not going to argue strongly for one technique or the other (this
discussion cropped up in Race Tech magazine a while back, and was
inconclusive) but my point is that skipping gears under braking is
*not* inherently a 'wrong' way to drive.  There are valid reasons for
*both* techniques.

Jonny

In theory, maybe. But in practice I would have to say no (partly
because I don't know the theory, but I know the practice). The brakes
can give X amount of braking force at maximum retardation (before the
brakes lock up), but the engine will also add to that an opposing
torque on the wheel, which will not develop a lock up because the
engine will stall. Grabbing the clutch thus stops the engine stalling,
but also removes the effect of engine braking, whereas the force from
the brakes remains the same. Blipping the throttle in a rocking motion
with your right foot allows you to select a lower gear and repeat the
process (it is difficult to left-foot brake when there is a clutch
down there too, and I don't have three legs, or a paddle-shift). The
only problem arises when the opposing torque from the engine is enough
to lock the driven wheels, and then you tend to lose control. Indeed
this is the problem, but it is a very rare occurence, usually in
reduced grip conditions.

Exactly right. A 5 to 2 shift will let the revs drop extremely low in
5th (meaning reduced engine braking anyway), before shooting up
towards the redline when 2nd is engaged. This has more chance of Bad
Things happening than a 5-4-3-2 where the revs are kept in the
midrange of the engine rev-band.

Yeah, but you need to replace the gearbox after doing it like a
hundred million times. Sure it will shorten the life, but it's like
taking a few days off the life of the universe, in exchange for a
couple tenths off your laptime.

That is a great example. The engine can produce enough opposing torque
to stop the car getting away from the driver even when the brakes have
long stopped working (due to overheating). That should give a clear
example of how powerful engine braking is.

Yeah, sure. Sorry, I started a bit of a rant about the state of
British roads there. Won't happen again.. well, actually it probably
will, but I will try to keep it under control :-)

Nick.

Jason

Brakes can be used mid-corner to tuck the front of the car in to the
apex, by just momentarily shifting weight forwards and loading up the
front tyres. This is a very useful thing to do, and is not slowing the
car down very much at all.

I have even heard of some drivers who use the brakes when accelerating
out of corners (in RWD, obviously) to actually stabilise the front end
of the car, control how much the rear slips out, and get better
traction. That is what inspired the MP4-13 McLaren CHEATING 2nd
braking system in 1998 (which they got away with and still only just
won the championship at the last race).

So, yeah. And I hardly need mention WRC drivers using the handbrake to
loosen the back end into hairpins, not to slow down.

Nick.

Just like suction fans, sliding skirts and six wheels were all
perfectly legal, once ;-)

Jonny

One rule states that you can only have one distinct braking system on
a car. McLaren had 2, one operating all four wheels, the other only
operating the rears. And they had two pedals, just to make it obvious.

Another rule states that no braking system can take the angle of the
steering wheel to alter the brake balance between wheels. McLaren used
the steering wheel angle to decide which rear wheel was on the inside
of the turn, and this wheel was braked more to slew the car around to
the inside of the track , and to act as a traction control device.
This constitutes four-wheel steering, which is as illegal as it gets.

These rules were in place well before 1998, but for some reason,
McLaren got away with breaking both of them.

Nick.