I think changable parts can be usefull to some extent.
But before it can be really usefull there must be "parts wear and tear".
Engine oil seems to be a bit over the top, but what about brake parts?
(Then also brake fade is needed
)
"Standard" for a good mix of durabillity and effect,
"GREEN" for good braking but not so lasting (just a example name (based on "Green stuff")
)
and "RED" for pretty good braking, but not linear brake effect (harder to get max effect witout locking the wheels), and good lasting.
Of course most people would go for RED, but then there also is a "skill" part.
Many other parts of a car can be made on the same "platform", for example suspension, but first must the orginal suspension setup be limited (to the tweaking possible in a real car).
And for those who wanna go elitish way, just go for standard parts
For gameplay all "good" parts must be penalized. The aliens will be the fastest out there anyway