I have a camaro for 4 year, and was always wondering, what is the bump on the passenger side floor ?

 

GM put that in the floor to make room for the pass. side catalytic convertor.

 

I think it is only there to make room for the catalytic converter on the V6 models.

Years ago (1996 I think), GM switched to a 2 catalytic converter setup (on the V8s). Since the V6s still used the single cat setup, this 'hump' space is still needed. I guess GM decided it would be too expensive to provide a different floor pan for the V8 models.