We already use non-original items here in Europe, such as camshafts and aftermarket modified followers…and, of course, ultimately, Retro cylinder heads

Hello Pete,
I believe only Roush Aviation in the USA manufactures the mentioned parts under PMA FAA approval. These parts are reversed engineered and are not manufactured under license/permission of Rolls Royce.
American PMA FAA parts are accepted replacement in the USA by the FAA but are only accepted without approval of EASA if they are non-critical flight items. I don’t think that Camshafts , Followers, Mayor engine castings are under this category.

If my memory serves me well, the Vickers Vimy replica original had Mercedes engines installed. When it flew to the USA, Mercedes started a lawsuit to prevent their engine being used as such over American soil. They re-engined it with American V-8’s.

Same for Boeing replicas of the Peashooter for which the Boeing Company forbid to use their name.

I can already see the Rolls Royce lawyers thinking of an accident caused by an Rolls Royce Merlin engine failure which could be traced back to an aftermarket part.

Ofcourse I am not an expert and could be wrong, so if you know such a Merlin flying around in Europe I would be more then interested, so I could see under which provisions they got their approval.

Pim

Early Birds Foundation Netherlands
Mustang P-51D, 44-74923