i found a place that can rebuild alternator and could upgrade the amps on it. If i get at least a 100 amp upgrade on the s4 alt will there be any mods that i would have to do to prevent any shorts or any problems that may occur? Pretty much will the s4 alt handle the upgrade?

 

You will be fine, just swapping to an fd alternator might be cheaper though.

 

yea but then it wont be plug n play

 

All you do is just stick two wires together to wire in the new plug, its quite simple. I just did the swap a few days ago. Either way, you will be fine, it's a good upgrade from the stock alternator!

 

Careful here. Using the same pulley you'll find that the volts will drop significantly at idle. Try and find a smaller pulley if you go this way.

You're best bet is to simply go with the FD retrofit.