Increased weight
Increased ride harshness
Increased cost
More expensive tires
Decreased performance

and that's just off the top of my head.....

then again 19's are blingalicious...

 

a typical track nerd/hobby racer's response who has a hard time dealing with the fact that no one cares about your laptimes unless your last name is schumacher/tsuchiya/hamilton/gordon.

 

so we will go with 3 out of 5 reasons. worse ride, cost more for the wheels, the tires cost more.

 

Wow, looks like I struck a nerve....

Just re-read my post and I never mentioned track use. All those points are important considerations for street use.

But hey, I can be open minded about this.

Turn the question around.

Why, (other than their aformentioned blingalicious nature) should the OP put 19's on the car??? Maybe you could list all the reasons you believe 19's are the better choice (rather than an ad hominem argument that fails to address any of my points).

 

you can have your B cups, i'll take the C-D.

 

OP back again . . . Thanks for the answers and comments . . . rennlist is a great place for answers, and never, never short of opinions either. Think I will send in membership fee today!

Regarding the wheel order--still with my winter wheels for a few months, but will pull out the VISA early next spring, but planning is 1/2 the fun

 

you can run 12s in the back on your c4s fyi, but not sure if champion makes the 18s in 12s. they dont' with their 19s on the 996 i believe the last time i checked when i was looking around.