He was a fighter plane "wrench" stationed in Britain,though my expertise leans more towards American fighters using the Packard variant of that engine.He called it "The Timber Terror"..lol.I still have vintage engine manuals he gave me 50yrs ago for the Packard Merlin(P51) and Wright 2800 radial(P47 Jug).

Yes,the Mossie was most impressive but the Rolls Merlin engine that powered it did not make it excel until the American company,Packard re-engineered it.

As you probably know,Britain offered a license to manufacture the engine to American car companies.Henry Ford had the contract locked up until he divulged his Libertarian nature by saying he would produce it only in defence of The USA(good for him).General Motors was also turned down.

Packard Motor Car Co. got the nod due to their reputation for excellence of engineering:("sure,we'll build it for ya.Just give us carte blanche")The result was a world beater that won the war!!

The inovations they made include what my uncle called "The Prestone Cooler" which helped cool the intake mixture from the dual stage supercharger Packard developed.There's also changes to engine bearing material that improved reliability.

http://en.wikipedia.org/wiki/Packard_V-1650