Im aware that stock my final drive is 4.2 was thinking of upgrading to mfactory 5.1 or even the 4.6 but what are pros and cons i drag race my car but also been looking into road racing i know the acceleration is better but is there that much of a noticeable down fall on the top end

 

Pros: Very noticeable gain in acceleration, better fuel economy, sounds cool.

Cons: Lower top speed in each gear.