When it comes to transmissions, words like gear ratio and final drive are thrown around a lot. Can changing gear rations give your car a higher top speed?
Few vehicle modifications have as major an impact as changing gear ratios, and it’s because your car’s gear ratio directly translates to how it delivers power. Think about it: The gear ratio, or how many times a driving gear needs to rotate in order to turn the driven gear once, determines how power from the engine is translated – either into acceleration or speed. For example, a 3:1 ratio means the input, or driving gear, spins three times for every one rotation of the output, or driven gear.
Higher gear ratios, like 4.11:1, are considered shorter. These provide more torque, but they decrease speed. On the flip side, lower gear ratios, like 3.08:1, are taller. These let your wheels turn more for each engine revolution, and they decrease torque, but increase the car’s potential top speed. The key word here is potential.
Just because you change to a taller gear ratio doesn’t necessarily guarantee a higher top speed. Your car still needs the right amount of horsepower to push through aerodynamic drag and rolling resistance at those higher speeds.
