Extreme Driving

When you change up a gear before it is needed, it can be termed as a Short Shift. In other words,  before using up the previous gear, you change up to a higher gear.

Why and when do you want to do this? This question is really valid because short shift almost always mean to say that you will be loosing some power and torque instantly due to being in a higher gear than it is absolutely necessary.

Tere are two main reasons for a short shift

1. The first reason is to purposefully take away torque from the wheels. Suppose it is a bump/slippery curve and it seems to be unable to utilize the full torque of the gear you would normally be in, so it might be a safer bet to be in a higher gear to reduce the likelihood of  a sudden wheel-spin, etc.
2. The second (and more common reason) is to save the time taken to change gear. May be you have a tight 2nd gear left-hand bend, followed by a long straight. You are at about 2/3 revs as you approach the apex. You can either stay in the second gear and use the extra torque to accelerate as quickly as possible or you can shift up to the 3rd gear before you need to start accelerating and sacrifice the extra acceleration for the time saving in not having to change gear.

An assessment has to be made as to analyze which would be quicker. In racing this is already tried and tested for a formula on the track you are racing on so that it can often be predecided. In rallying this is less clear, and mostly of slightly less importance.

In rallying, the main reason you would use short-shifting would be for balance rather than outright time and speed. If there is a twisty turn ahead for the next 50 yards and that you will need 1 up change in the middle of it, you can decide to get the change done before the complex twist to avoid upsetting the car mid-way through it.

A Visual Aid For Shifting Right!

Hand position while shifting

While shifting from the top of the box to the bottom, form an open cup with your palm, and place over the shift knob with the inside of your fingers and the palm of your hand making contact. Guide the lever quickly with your fingers, but don’t strong arm it. Gently push it, but don’t slam. The movement is primarily with the wrist. If you lock your wrist around the shifter like a fighter plane control stick, you will actually slow down your shift.

Passing is not allowed in most club racing of the hot lapping or time trailing varieties.  Autocrossing doesn’t involve passing at all.  However, there are some things to know in a racing that involves passing, or in a situation where passing in a corner is unavoidable or inevitable.

Passing can be achieved successfully under three situations:

• You use your car’s greater horsepower or momentum when exiting a corner to pass on a straight.
• You  pass under braking by controlling the preferred driving line while entering a corner.
• You take advantage of your opponent’s mistakes.

Likewise, there are some rules for safe passing.

1. The responsibility lies on the shoulders of the driver initiating the pass to ensure that it is done safely. The opponent should be aware of  the manner ‘Where you pass’ and ‘How you pass’
2. It is illegal to block. Veering, whether it is 10 inches or may be 10 feet, to keep another car from getting beside yours is blocking. In most races, the organizations allow you a single move to protect your position, but repeated left right movement is considered as blocking.
3. If a driver illicitly manage to take his car beside your car, give room for the other car to carry a line thru the corner. It is not necessary to give him the optimum line, but cutting the car off that results in forcing and of course it is considered as poor racing. And if the officials notice it as deliberate, you might be fined or subjected to penalty. Racing is not a roller derby. Elimination of your competition is never and objective.

It needs a lot of planning while passing under braking or on a straight close to a corner, than a simple pass on in the middle of a long straight.  The objective of passing in the braking zone is to control the inside line to the upcoming corner. To keep your driving line through the corner when placing you car between the other car and the corner apex, the other car must yield to give you room. The preferred line into the corner can be essentially “controlled” in this manner. The potential drawback of this method is that your car will not be keeping the car in the optimum line thru the turn.  Even if you control the corner entry, but if you have to slow down too much in between, or make an apex too early, the car which you have just passed may speed up or get a better exit line, and pass your car right when exiting out of the corner.

Practice sessions might be forcing you not only to practice the optimum racing line for fast laps when the track is clear of traffic, but you also will want to practice some passing lines. Move to the inside from the edge of the track normally you would be driving, brake a little farther and then turn in a little later. Practice taking a line that will put your car in the middle of the track while coming out of the corner, or a least far enough over from the edge so as not to leave enough room to be passed for other cars on the exit. (Hogging the road so that there is not enough room to pass, but still avoiding veering/swerving, is not considered as blocking).  To reduce the chance of causing an accident when attempting a pass during the race, you should practice the passing lines and be familiar with the passing lines.

A Visual Aid For Cornering Right!

Approaching a corner

Maximize the potential radius by approaching the corner on the edge of the track. You can see that the turn in point for this corner is about one full car length pass the brake marker in front of the car.  At this point, you should almost complete the braking and should be easing smoothly off the brakes.

Midway of cornering

Midway between the turn in and the apex. at this point the driver needs to maintain a constant speed. Using a late apex line, the driver will begin to accelerate in about another two car lengths into the turn from this image.

Apex of a corner

Like most simple corners on the track, the apex of this corner is slightly late. The apex is said to be the point at which the car reaches the inside most position of the turn. At this point, the driver is almost full on the gas. (Make a note that the second car is very wide, and is not likely to touch the curb marker without slowing down significantly).

Coming off the apex

Coming off the apex, the car is now headed to the opposite side of the track. At this point the driver should be at full throttle.

Exiting a corner

The corner exit should be taken as wide as possible. The driver can use the corner markers as part of the track, if the corner markers are flat enough, and not excessively slippery. However, the driver needs to be careful with tall curbs as they can suck the car up very quickly.

Road racing comes down to cornering in the end. The driver who is able to sustain the highest speeds through the turns will have the lowest lap times, assuming the cars to be of equal configuration.

Braking and accelerating into and out of a typical corner. Note the pedal pressure variation  during the course of cornering.

To get familiar with the terminology first, every corner is made of three parts. They can be termed as the entry, the apex and the exit.

The entry is the point at which a turning begins. The apex can be defined as the point where the car reaches the furthest point on the inside of the turn. It is at the exit where the car completes the turn and start to drive straight. While driving through a corner or a series of corners, the main objective is to have the maximum possible speed at the exit of corner, or at the last corner of a series. It is not necessary to have the maximum speed

The objective in driving through a corner, or a series of corners, is to have the fastest possible speed at the exit of corner, or the last corner of a series. It is not necessarily to have the fastest speed going into the corner, nor even the fastest speed in the middle of the corner. The last corner exit before a straight is the most important segment. The speed of the exit determines the speed during and at the end of the straight. If you can increase the average speed of an entire straight, that will have greater impact that a faster average over the shorter distance of the entry to the turn, or through the turn itself. The path, or “line” you drive through a corner will determine the exit speed. In general, the fastest line through a corner is the one that allows the greatest radius, or straightest path. As a car can go faster around a large corner than it can around a tight corner, the shortest path around a corner is rarely the fastest. To illustrate these concepts so far, the classic teaching aid is to look at a 90-degree bend. In the illustration below, the dotted line follows the path of the road. The solid line indicates a path that maximizes the radius of the turn, or attempts to make the turn as straight as possible. As you can see there is significant difference in the tightness of the turn that follows even the outside of the road compared to the one that utilizes the whole width of the road surface.

Cornering

As mentioned, the objective in any corner is to have the highest exit speed. Taking a line that allows the earliest possible point to get back into the throttle is also involved apart from increasing the corner radius. In order to do this, the car should straighten  back out on the corner exit path at the earliest. The above corner line can be modified further to allow this. In the image below, the previously mentioned large radius path is illustrated by the dotted line. The solid colored line indicates a path known as the “late apex”. This path moves forward to the point at which the car reaches the corner apex. The exit path of the car gets straightened by the late apex, and therefore allows the driver to accelerate earlier. This helps to increase the exit speed, and it in effect helps to lengthen the straight, that allows to achieve higher speed at the end of the straight.

Ideal Line

There is still a faster technique for most of the corners, while the geometric racing line is faster than the natural line of the road. The theory behind the technique is using the late apex. The car can aim to apex later than the geometric apex point, by delaying the turn in point, and beginning the turn with a slightly sharper bend. This helps to straighten out the second part of the turn, and thus allows the driver to throttle early. Even though the car will have to slow down more at the turn in phase, the exit speed will be higher. This exit speed helps the driver to achieve that much more speed on the straight, which will bring down the overall lap times.

Winter driving is considered as one of the toughest task in the field of driving. In case of winter driving, front wheel drive cars, rear wheel drive cars and all wheel drive cars behave differently. Be certain that a driver know how a particular type of car will react to driving situations and respond to the driver’s inputs.

In icy conditions, it is recommended to follow these guidelines :

• Do one thing at a time
• Brake only in straight line
• “Coast” thought corners on a steady throttle
• Accelerate when you are through the corner

Especially under slippery conditions, centrifugal force is your enemy. The centrifugal force increases with increase in speed and / or reduced radius in a corner.

Beware of wide tires as they will hydroplane sooner / more than narrow tyres due to the wider contact patch.

A driver should be sure of the correct skid control techniques for his type of car. First make sure where the driver wants to go, steer to where the driver want to go and release the gas pedal gently to allow the contact patches and to regain traction. DON’T BRAKE.

It can be said that braking around a corner is an art in driving. When a driver applies the brake, weight is transferred forwards from the back wheels to the front wheels. In a corner the weight is transferred outwards from the inside wheels to the outside wheels. To get the handling balance required, the designers adjust the front and rear spring stiffness accordingly.

If you try to brake hard and corner at the same time, it will be pretty easy to lock the inside rear wheel and start a spin. Even the sudden removal of power from a front wheel drive car in mid corner can initialize a spin.

It is possible to brake gently in corner and keep control. But in case of an emergency in the mid corner, a driver is force to brake hard, loss of control is much more likely than if the driver was braking in a straight line. It is always safe for the driver to brake before the corner than halfway round the corner.

A driver won’t be able to steer any more, if the drive gets the front wheel locked due to heavy braking. Anti-lock Braking System (ABS) automatically keep the tires on the point of locking so that the driver can continue to steer and thus slow down.

Cadence braking can be used if the car lacks ABS, whereby the driver lock the wheels, then release the brakes so that the driver can steer, brake again, release and steer again in a sequence until he has avoided the hazard. The cadence braking is specifically useful on slippery roads, but it gets out of sheer practice and quick response (reflex) to be able to release the brakes when the driver feels sliding towards the hazard.

Braking distance is an important factor in driving. Reaction times for a racing driver will be around 0.25 seconds but perhaps for an older person whose mind and legs are not as agile is one second.

The best braking deceleration is generally considered as 1g. 1g is the retardation due to gravity if you throw a stone into the air. More fierce braking (1.0g – 1.2g) than this is possible for some cars as tires key into road surface than rub across.

Thinking distance (reaction distance) plus braking distance is the recommended stopping distance. The Highway Code assumes that the reaction time of an average driver is 0.7 seconds to think and then the driver can operate the brake pedal. The reaction time for a driver at 30 mph is 30 feet, 40 feet at 40 mph etc. A car at 30 mph stops in 30 feet while braking at 1g.  In order for a gradual build-up to maximum braking in practice, the Highway Code distances are calculated at 0.7g (43 feet from 30 mph). With 0.25 second reaction time and good road car brakes, a racing car driver might stop from 30 mph in 11 + 25 = 37 feet, while with 1 second reaction time and normal car braked, an older person would need 44 + 43 = 87 feet.

Increase of  braking distance is as speed x speed – so 43 feet from 30 mph is 172 feet from 60 mph. So it is always recommended to keep your safe distance from the car in your front. While traveling on fast roads, the safest is to leave at least two seconds between the car in front and your own car passing the same spot. It needs to be more if the road is slippery.

Accelerating from a stand still is an art of engine revs and wheel spin. Accelerate in a professional way is considered as smooth acceleration.

The engine will bog down and the driver will not be providing the tires with atleast an optimum torque they can deliver on the road. But if the engines revs are too high, the driver will exceed the maximum torque, this by spinning the wheels.

The driver will get the maximum possible acceleration, if the driver can balance accurately between Traction and Torque. This is not really possible every time in the real world.

Since the changes in road surface have a greater effect at slow speeds, especially when the car is in first gear and therefore putting maximum torque to the wheels,a driver will have to be complete god to accurately and instantly adjust the clutch and throttle to account for smooth acceleration by keeping the traction vs. torque at the maximum. The only way to achieve this is by revving the engine to high rpm and balance using the clutch. The real problem here is that the clutch will last about ten minutes if the driver keeps that up.

Thus, using a controlled wheel spin is the best method, for this reason. Build the revs up to just into the power band. Smoothly let out the clutch so that the wheels gradually start to spin and balance the spin to be just before they are starting to bite again. Keep this up until the car is at a high enough speed that the wheels could grip and would still be in the power band.