stock enthusiast radio system...

[Viggy75]

i wanna hook up an amp to it whats the max watts it could handle?

[Viggy75]

.

[the converted]

Ummmm 20? They aren't designed to have a lot of power put into them. You'll also probably benefit a lot more if you replace the speakers as well, because they are going to make the biggest difference in what you will hear.

[EW]

i wanna hook up an amp to it whats the max watts it could handle?

Most factory $3 speakers will handle 40 watts RMS or so. If the amp has an adjustable highpass crossover, you can protect the speakers from the low bass signals they are not designed to play.