Originally Posted by
nomorecatering
What's to stop you taking a servicable Merlin engine to a company that desihns and built high tech racing engines and getting them to pull your engine apart, measure everything, do new drawings and building new parts.
Exactly what Roush Racing did in the USA....and as said, Retro Track & Air have done in the UK....although Retro Track & Air in UK have gone as far as casting new Merlin cylinder heads.....and I guess RR are probably OK with it, given IIRC, its is Retro Track & Air that do the Merlin rebuilds for BBMF.