If you want to know what you can make maximum on 93 octane pump gas only with bolt-ons, it's around 400 whp depending on dyno, and it's not a setup you'd want to sustain for any extended length of time. Expect maybe a 100-110 whp delta over stock at best.
On methanol/E85 or both you can squeeze 440-450 on a dyno glory run. Real-world expectation targets with consistency are closer to 430 max.
E90 LCI N54 6AT