Lovely work! A few years ago I heard of a similar project, creating a 1/3 scale Napier Dagger, which is further along.

http://modelengineeringwebsite.com/Napier_aero_engine.html

http://modelengineeringwebsite.com/Dagger_update_2.html

“There are no castings and all parts are hand machined from solid alloy blocks”

Jaw-dropping.