For those who have supercharged their Max's, will the stock internals
be capable of handling the extra boost? Anyone upgrade their internals? Thanks in advance.

 

How high of boost are you planning to go? Your tranny will probably blow before your engine. You'd have to check custom everything if you want to upgrade your internals as there are no parts currently for the Maxima

 

The internels will be fine to about 12 psi. Though the tranny will not, for long. That goes for a 5 speed or auto.