What Allmotor said! I'd add that on Vitviper's old site, he turbocharged a 9th gen Si (K24) and said that the stock engine can handle 400 HP reliably, so he tuned the one he was building to around 360 HP or 370 HP to leave a safety margin...can't recall which. I would not exceed Vit's numbers under any circumstances as he's forgotten more about this than most of us will ever know. A good tuner should also tune the midrange carefully so you have extra power, but it doesn't spike hard a lower RPMs, in order to protect the transmission. You want the maximum meat high enough in the rev range to safely spread out the load.
A well thought out, properly designed and properly installed kit should keep nagging issues to a minimum, but be prepared...
Along with the clutch, i believe you'll need to either 1) replace the rear, lower torque/engine mount, or 2) do a I did in our 2015 and fill the mount(s) (I did rear/lower and the top). I replaced the mounts with racing mounts but since it was a daily driver, I couldn't deal with the excess shaking and vibration. Again, following the wisdom of Vitviper, I filled the stock mounts, which provided about 90% of the rigidity while keeping about 90% of the comfort of stock. It worked far better than I'd have imagined with virtually zero front-end hop due to the engine bouncing around. This also keeps us from cracking, dislodging or otherwise damaging the exhaust system, downpipes, etc. You can find youtube videos on how to do it properly, which was quite easy.
I hope that this proves helpful. Good luck and have fun!
