I have heard discussion that the bigger, physically your gears are, you can gain some power, or torque. Im not sure im going about this question properly. But if someone could shed some light on this subject it would be appreciated.

It would be the same gear ratio. 3.73 just larged ring and pinion gears.

Chris,  

The answer to that is NO. However the bigger the more durable it is.  smaller and lighter is always faster if you can get it to hold together.
 Chosing a higher gear ratio where as you can run trans in high gear will transfer more power and torque to rear but will still be a very small increase. if you are having no trouble and like the ratio you have I see no reason to spend time and money on rear gears. put in on something else maybe a new carb, valve springs, camshaft or something to get better engine performance.