Grand Mark?
 

I have a 99 MGM and was thinking about putting new rear gears in, But i was wondering if any1 knows what gears are in it now, and if it will make that much of a difference?

http://c3.ac-images.myspacecdn.com/i...7f44acbbb2.jpg

check out This Post for finding out your axle ratio and the performance thread for more info on lots of stuff.

Gears can make a night and day difference pending on what gears you currently have... Keep in mind you;ll have to change the gear on the speedometer as well so that it is correct