The Right Gear
The IAM recently recommended using lower gears in 30mph zones. Here Julian Smith from Ride Drive explains how to choose the correct gear for the situation
Ride Drive does advocate the holding of lower gears to enhance the ability of a driver to maintain absolute control of a car and to facilitate a smooth and flowing drive. To explain matters in more depth, without getting to be an anorak here, I will deal firstly with the 30mph thing – or at least the lower end of the speed limit scale.
In Times Gone By...
When cars first became available to the masses they were, by today’s standards, quite primitive machines. 4.5 litres then only produced a fraction of the horsepower that a 4.5 litre engine will do now. In fact a modern 1.2 Micra will probably out run one of those old big-engined boneshakers, but 4.5 litres were not the norm were they?
Engine sizes for the family car from around the 1950’s were more in the like of 1098cc, 1800cc or 2 litre and because the torque and relative power output was low by modern standards the manufactures had to balance the engine output with an appropriately gauged range of gears.
Consequently the gears were fairly low and close in ratio, the price of fuel didn’t really matter at 3 shillings a gallon, the car would pull from 30mph in top gear (which in those days was 4th gear) and everyone was happy – that is except the owners of the 1500cc Austin Maxi, which was one of the first cars to have a 5-speed gearbox but insufficient power to sustain speed in fifth!
Modern Day
If we come back to the modern day the concerns of the car manufacturer, inline with public demand, are somewhat different. For one thing, and because the price of petrol has become the equivalent to that of the same quantity of liquid gold, we all want to get that extra couple of miles out of a gallon. Also, because the torque range of engines has become wider and the gearing has become higher it may be that with certain models a higher road-speed may be required before the next sequential gear is required.
I drove a 1.7 new(ish) Vauxhall Astra Turbo Diesel the other day, and whilst there is nothing to boast about in doing this, the car, I found, is virtually impossible to drive on the flat at 30mph in 4th gear. It doesn’t like it at all! Therefore you are forced to use third as your top ratio and anyone that does use 4th in one of these will almost certainly have to break the speed limit in order to do so.
So what is the harm in using third? Where does it say, “Thou shalt always arrive at the highest gear in the gearbox when driving your car down the road?” Gears are there to assist you in getting the best out of a car in terms of performance, to be able to use it effectively as a means of transport.
An Analogy
If you tried to ride a bicycle with the idea that you have to reach to highest available gear in the lowest amount of time you would soon change your tune, because it is you and not the engine that is having to work harder than is necessary.
Sticking with the bike thing for a moment, in what mode would you ride so as to expend the least amount of effort and energy? The answer would be to ride with your pedals moving at a moderate speed and with sufficient momentum to sustain the road speed that was comfortable. This would be at a speed you could sustain over a prolonged period without having to heave the pedals around or, conversely, have your feet whizzing so fast you couldn’t keep up with yourself.
The same applies to a car engine. That Vauxhall Astra was far more comfortable doing 30mph in third than in 4th and required less energy to maintain that speed. If it was using less energy it was using less fuel and there was less stress on the machinery. Not only that, by use of that 3rd gear, I was able to make the necessary changes in speed to meet the requirements of driving in traffic, by easing or squeezing the accelerator, often removing the necessity to brake.
It also meant that the I could easily keep the car to within 30mph whilst driving moderate up and down gradients in the road, again without the need to make further gear changes or to make applications of the brakes. If you are not braking you are reducing the amount of wasted energy, and if you are not wasting energy you are saving on fuel, tyre wear, wear on brake components – the list goes on. Not everyone drives Vauxhall Astras and each car will have its own gearing characteristics. I have driven many different types of car and not found any that complains about being driven in 3rd gear at 30mph.
Choose Your Gear
At Ride Drive we often have clients that find it difficult to maintain a speed in their car that is within a low speed limit and as the session progresses we encourage them to get used to using third gear in that environment. It is such a nice flexible gear and you can do so much with it.
Driving in town is not the only place where the third gear helps produce a smooth and flowing drive. Imagine you are coming up to the end of a 30mph zone into a National limit area that is on a B-class or C-class road, and after a short straight there are two bends, separated by a short straight, and then a fairly straight road for about a mile. Holding the car in 3rd you can accelerate smoothly and comfortably from your restricted speed of 30mph to a higher speed. Still holding in 3rd you can begin to back off the throttle on approach to the first bend, at just the right time so that when you reach it the car is travelling at the desired speed to negotiate it safely. As you are still in 3rd gear you can now balance the car on the throttle for the duration of the curve and then use the gear to accelerate off the bend.
Still holding 3rd you decelerate the car again for the second bend that comes up shortly after the first, and using the same technique, you driver around the curve accelerating again on the far side. Now you are on the long straight section it becomes more appropriate to use the higher gears as required. What you will have done here is used acceleration sense in conjunction with the effective use of the gearbox to deliver a brisk, but smooth flowing drive that has been achieved with the maximum degree of control and with the least amount of stress being placed upon you or the vehicle. Remember also that changing down a gear is not automatically linked to a reduction in speed. It is often desirable and more effective to select a lower gear, but maintain a constant road speed. It just gives that little extra degree of car control when dealing with areas of potential difficulty or danger.
Autos
What about automatic gearboxes then? There has been no mention of them so far and yet more and more cars these days have them. How do you drive with an automatic box? Has anyone ever taught you what to do with it other then stick it in ‘D’ and press the accelerator?
One case that I have personal experience of illustrates how effective the efficient use of an auto-box can be of benefit was that of a client we served about 2-years ago who was a chauffeur to the director of a large business conglomerate. He was doing a 3-day course and had brought along the ‘company’ car. The vehicle was a BMW 750 stretched and armoured limousine with automatic transmission. Like one of the Royal Navy’s finest aircraft carriers, the car probably weighed in at about the same tonnage – well nearly. I was running the job on this particular day, his first day on the road, and as we left the urban environment, in which we started, onto a nice playful B-class road I said to Nick, “Okay Nick, let’s see a nice progressive drive keeping it all nice and smooth.”
Smoothly Does It
As we went through the de-restriction signs we accelerated up to 60 before reaching the first of many bends, and with many different gradients to come as well. There was much huffing and puffing coming from the drivers’ side as he literally fought with the beast along that road. He was finding it very much hard work and after letting him suffer for about 10 minutes I suggested to him that he might find it easier if he were to manually select 3rd gear, and to remain in that gear until the road environment changed and told us it was appropriate to do otherwise.
Well the difference it made was fantastic. Instead of endlessly coasting on the car now actually decelerated when Nick lifted his right foot, and by introducing acceleration sense and advanced road positioning as well he was now able to set the car up for bends and corners often without having to brake – and still push along quite nicely too. He was no longer fighting with the car. He was making the car work for him.
Overtaking
Another example of effective driving with an auto-box is the overtaking manoeuvre. Many a driver has been heard to complain that the kick-down with an automatic takes too long and is a nuisance. Well, you can eliminate kick down all together and get the same response for the car as you would with a manual transmission. All you have to do is decide what gear the car would select, at your current road-speed to accelerate passed the vehicle you are going to overtake. Having worked that out, select that same gear manually so that when you do go for the overtake the car will respond at the required rate immediately.
Just side-stepping for a moment, it never ceases to amaze me the number of drivers that you see going for an overtake on a two-way road in 5th gear. You can spot them a mile away as they are the ones that take about 10 days to get passed anything and then get flashed by the oncoming driver who has had to make room for them to get back in. That signals another problem. How many drivers out there were never taught how to overtake?
Anyway, going back to HMS Ark Royal and again arriving at an urban environment, Nick was encouraged to manually select and hold a gear. Immediately the lumbering great beast became so completely manageable it was as easy to drive as a car many times smaller. By choosing the right options there is so much less stress involved in driving, and not only that, there is less stress on the vehicle, which means less running costs and you are in control.
Julian Smith
(Ride Drive Limited)
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