11:1+ is nuts. 10:1 looks to be streetable. Apparently Marco swears by higher compression pistons. Just gotta tune it well and use some good gas. Or 94 with lots of meth.

And also what Corte said. I believe it's at like 600whp that after that things become super expensive as you need to upgrade your fuel system, drive train, plus things just break a lot quicker at higher power levels.

Plus, with larger clearances, including bearings, there's a lot more wear on cold start. At those power levels, it won't make sense to drive the car on anything other than a Sunday to and back from the track.