the only way your warranty will be void is if the part you install directly causes failure to the part that you want to warranty. for example....if you install a supercharger and you blow the engine, it is void. but if you want to warranty a faulty wiper motor, you are ok.
mods like an intake would usually be ok with your dealer. superchargers are a different story. do a search and you will find this has been covered before and many questions you may have will be answered.