the higher the gear ratio the faster the car goes? is this true?

Answer 1

Perhaps. if it has enough power. You can raise the ratio too far and in doing do decrease the amount of torque that reaches the wheels thus lowering your top speed.

Answer 2

First, let's talk about engines, transmissions, and speed. The engine has a relatively narrow range of RPM (revolutions per minute) in which it is effective: generally between 1000 (at an idle) to 5000+ (the "red-line"). However, the car has a wide range of speeds it must accomodate (from an idle to 80+ MPH). To allow the engine to stay in it's "power band" (the RPM range where the engine runs best) the transmission has several ratios from the engine to the wheels (not including the differential). Also, the higher the ratio, the more torque is available at the wheels (through mechanical advantage)

Let's imagine a transmission with these ratios:
1st - 5:1
2nd - 3.5:1
3rd - 2.2:1
4th - 1.5:1
5th - 0.9:1

So, when in 1st gear, the engine turns 5 times for every turn of the output shaft of the transmission. As you can see, the higher the gear the lower the ratio. In this case, 5th gear is "overdrive", meaning that you get more than one turn of the output shaft for one turn of the engine.

The faster the output shaft turns, the faster the wheels turn. The faster the wheels turn, the faster the car goes.

Therefore, the lower the gear ratio, the faster you go. Right?.... Well, almost. There's one other factor which must be considered: Wind resistance.

The faster you go the more the air pushes on the car. This is the effect you experience when you hang your hand out the car window. You'll notice that the "pull" from the wind is much stronger at 80 MPH than at 60 MPH. The faster you go, the more wind resistance. If you "floored" it in your top gear you may not produce enough torque to overcome the full resistance of the wind. It is possible that you may have to drop into a lower gear to gain this greater torque. There's no rule about this, but I find it to be true sometimes (it depends upon the top speed and the gear ratios).

Sorry there's no black-and-white answer to your question, but I'd say this:
The lowest gear ratio makes it possible for the wheels to turn faster while the engine turns slower.

Answer 3

No, not at all. It's much more complicated than that.

A higher gear ratio CAN increase the acceleration times and top end speed, but as with all things there's a torque trade-off to consider that may negatively affect driveability.

Read the article below for some basics:

Answer 4

Potentially, in a world with no friction, yes. In this world though you would eventually get a high enough gear that the vehicle wouldn't have power enough to pull its own weight.

Lower gears, power. Less speed.
Higher gears, speed. Less power.

In overdrive you might have a 0.75 to one ratio. For every revolution of the motor you get 1.25 from the tires.

Now imagine a really high ratio. let's say for each time the engine turns over, the tires are trying to turn 25 times. See the problem? Engine would lug down and die.

Answer 5

The high gear in most cars is overdrive for better gas mileage now days. A lot of them will go faster in the next gear down, since the engine doesn't have the power to go very fast in the top gear.

Answer 6

No. Its the opposite. 5 to 1 means motor makes 5 turns while the wheels make 1. Smaller is qyuicker because 2 to 1 means the motor makes only 2 turns for the wheels to make 1.

Answer 7

As long as you don't exceed the torque rating of the engine , yes, you are correct. If you do exceed the torque specs however you will not go at all and your engine will stall.

Answer 8

Your best bet is to just not mess with it at all.