I don’t see the 39/35 valve size as a problem at all. What’s the port spec?

190hp out of a 2.0? That would qualify you in the back of the pack in U.S., everything else being equal. Are ti parts free? Compression? Fuel? How about flywheels and clutches?

As far as 9k with 906 cams... me thinks that’s a fairy tale. 906 cams simply won’t do that.

We were testing to 9500 several years ago and wearing the valve guides out every 5 hours. Now we cap at 8500. A strong 2.0 easily makes 230+hp. But just as important is getting reciprocating/rotating mass way down.