The principles of gearing ratios as it affects an automobile and indeed its performance is one subject that has been largely misunderstood for a long period of time, the speed of a car is not exactly dependent on the size or complexity of its engine as believed by a cross-section of an automotive enthusiast but rather how well its gears are ratioed.
We'll take a close look at a car,s gearing ratios and how exactly this system affects its speed and overall performance.
WHAT EXACTLY IS A GEAR RATIO
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Gear ratio or better still velocity ratio as it can also be termed is simply the ratio of the number of teeth on the driven gear to that of the driver gear, this determines how fast or slow the driven gear spin, now let's put this in a simpler perspective with a simple example which is a bicycle chain, a bicycle chain has got two gears the driver and the driven gears lets say the driver gear has got about 20 teeth and the driven gear has also got 10 teeth is simple to say that as the driven gear would turn twice as fast as the driver gear thus multiplying its speed with the rider applying less torque or force to the pedals.
Stay informed with our next post on types of automobile transmission gears.
HOW DOES GEAR-GEAR RATIO AFFECT YOUR CAR PERFORMANCE
Gears are ratioed in automobile transmission simply because of two variables, to either multiply the speed or increase its torque (power) it's just as basic as that, now how does that really affect your car performance.
An automobile transmission particularly the manual tranny comprises input and output shafts, the input shaft is directly driven by the engine while the output shaft connects to the wheels, these two
components are directly connected by the gears which determine the speed at which they turn in a typical manual 5-speed transmission your first second and third gears ensure that the output shafts turn a bit slower than the input shifts resulting in a bit more torque (power) than speed, the fourth gear which is what we call the direct drive ensures that speed of the output and input shafts matches each other, the fifth gear which is known as overdrive simply ensures that the speed of the output shafts becomes a bit higher than that of the input shaft equalling more speed and fuel economy. the reason why you do not have to rev your engine high enough to attain maximum speed in the fifth or overdrive gear.
Let's break this down for a much better understanding.
Ist Gear (Gear 1) A ratio of 4:1 with the input shaft gear. mainly for torque (power), your take-off gear
2nd Gear(Gear 2) A ratio 3:1 with the input shaft gear for power and momentum ( better used for climbing hills and steeps)
3rd Gear (Gear 3) A ratio 2:1 with the input shaft gear for acceleration and speed build-up
4th Gear (Gear 4) A ratio 1:1 with the input shaft for speed and fuel economy ( direct drive)
5th Gear ( Gear 5) A ratio of 1:2 for speed, acceleration, and better fuel economy (Overdrive)
RECAP
Gears in automobiles are simply designed to improve the speed fuel efficiency and performance of engines.
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