[Ck.ivan]

So I found someone willing to sell their Type R wheels for a steal, great condition, wanted to see if anyone was running wheels that big?

 

[BWill9886]

Well your first problem will be that Type-R's run a 5x120 bolt pattern, while your Si runs a 5x114.3. They are sized for an M14 bolt instead of an M12 as well.

Other than that, take a look in the wheel fitment threads. I'm sure someone is running something that big.

 

[Squidward]

Aside from fitment issues, I would also caution that this would likely look very silly and result in a miserable ride quality.