No don't mod the car thats how you start to rag it out. If you want a car that you can put an intake or exhaust on get a honda or acura big body lexus just rims, system and cruise with window rolled down. B)
I got a 06 gs 300 with factory 18" chrome rides just fine give the car a more agressive look too. I wanted to get the 18" chrome five star that comes on the gs 430 but the dealer tod me that they couldn't hook me up.
Lexus also got a tire and rim program that replaces your rime or tires if you should damage them due to road hazards pretty cheap too.