I know that the 3" y-pipe is recommended for supercharged/nosed Maximas. So, would it be a waste for non supercharged/nosed Maximas to have this? Or is it better to just stick with the regular Cattman y-pipe? Would that be a waste if you do plan to get a supercharger later on?

 

It could actually decrease your low end A LOT on a N/A car...becuase the exhaust gas doesn't flow quickly enough. I would stick with the regular 2.5 inch if you don't plan on going the forced induction route. If you do plan on doing a S/C or NOS....then get the 3 inch...it's not going to hurt your car, it will just not preform as well as the normal one.