You're car would not drive without rims. Try it, I dare you. I can and have changed my own oil so Idk what you're talking about.
Also parts don't have to improve the performance of your car at all. A car is made up of hundreds of different parts that work together to make it run. What you're talking about are aftermarket parts to replace factory parts. More specifically ones designed to improve performance. Rims can be used to improve performance too if you get the right ones.
