[owalker06]

what is the difference between the 3:73 gears and the 4:10 gears, and how do they differ from the stock gears .

[coppah37]

3:73= 3.73 turns of pinion/driveshaft to 1 turn of wheels
4:10= 4.10 turns of pinon/driveshaft to 1 turn of wheels

In other words your driveshaft will turn 4.10 times to make the wheels turn once. Both will give you better acceleration over the stock gears utilizing more power from your car. Also they will have a higher rpm at cruising speeds.