Rotax 912is vs. 915is

This may be a dumb question but can you replace the 912is in an RV-12 with a Rotax 915is after certification? Any obstacles that cannot be overcome?

Or maybe better yet... can you modify a 912is to produce similar performance to the 915is?

912iS with 915is Performance

Very doable, Edge Performance in Norway has the solution you are looking for.
Upgrading the 912iS to equivalent performance of a 915iS would probably be much simpler than converting the entire firewall forward to a 915iS.

https://shop.edgeperformance.no/no/

https://www.facebook.com/edgeperformance.no/

http://badasspowersports.com/