sslude

i dont want that one website howstuffworks, it didnt help e. i just want to know what they show, if it is etter with shorter gear ratios. like if it is a short gear ratio, is it the distance between the gears? and also, what is a final drive?

sslude

anyone?

Cynical 1

http://www.google.com/custom?q=gear+...=theoldone.com

sslude

i dont have the time to really read throguht hat, can someone just explain it. not like every detail, but like an overview of what they are.

RaceTilIDie

1:1 gear ratio is when the motor is spining at the same rate as the wheels. In most cases, this is 1 gear less than the total number of gears. In a 5 speed, 4th is 1:1. The more gears you have (close ratio) before the 1:1, the better you can take advantage of your torque band, for better acceleration. Overdrive is when the wheels spin faster than the motor, for better gas mileage. Is this what you are asking?

project_mercy

You can get a mild explanation here:

http://people.clemson.edu/~btoy/tech/TECH2/tech2.htm

Edit: that page is better than my explanation


[Modified by project_mercy, 11:03 PM 1/3/2003]

Cynical 1

Honestly, if you don't have time to read through info that we give you, and research, how do you expect to learn?

It will only take 10-15 minutes to read one of the links that we have given you.

I'm not flaming or being a dick. But, research is key here to find out how things work.

Weston

Actually, it's not really overdrive, since the final drive gear eliminates it.

Here's an explaination:

Think of it as 2 gears being used at a time inside the transmission... You have the gear you're "in" such as 1st, 2nd, 3rd, etc and you have the final drive. The final drive gear is not selectable and it's always in use. The effective gear ratio can be calculated by taking the current gear ratio and multiplying it with the final drive ratio. For example, if the gear ratio is 3.000 and the final drive is 4.000, then the actual ratio between the engine and wheels is 12.000... that means for every 12 rotations of the engine, there is one rotation of the wheels. It also means that the actual torque at the wheels is 12 times the torque that's at the crank, minus drive train losses. Side note: dynos don't measure true "wheel torque" (they factor out the gearing).

Gearing just trades engine rpms for torque at the wheels. Shorter gears (ie higher ratio numbers) means there's more torque at the wheels but requires the engine to be running at a higher rpm. You're really putting the most power to the ground in 1st gear, but your engine can only spin so fast (ie redline), so you're forced to shift into a higher gear to bring the engine rpms back down. A higher redline makes you faster because you can stay in a lower gear longer. But, if you're torque drops off quite a bit at higher rpms, it may be better to just shift and get the rpms back down into the powerband... that depends on the engine & transmission, and it's something that you'd have to calculate. In the case of the 3rd gen Integra LS, it's still beneficial to shift at 7100 rpm even though it's power drops off above 6k rpm.

The Integra GS-R is faster than the LS only because it has shorter gearing and a higher redline (VTEC gives it a powerband that makes that feasible). It's horsepower rating is higher because of the high redline. Horsepower is calculated based on torque and rpm. Having your powerband at higher rpms produces a more favorable horsepower rating. But it's hardly a perfect measure for comparing two cars.




[Modified by Weston, 9:29 PM 1/3/2003]