It's always worth asking at a decent dealer, you might find an enthusiast who is willing to help.
The Ecotec engine in my 4/4 is a GM/Vauxhall/Opel unit, and when I went in to my local Vauxhall main dealer to order timing belt and cam wheels for it they were fascinated that I had a Z18XER engine in a Morgan. A couple of them trooped out to have a look at it, pointed out the non-standard components (of which there are hardly any) which was very helpful and then made me an honorary member of the Sri Owner's Club so they could give me a 10% discount. Good lads.
I'm puzzled by this post. Michael Palmer's book "Morgan 4/4 The First 75 years" doesn't list any GM engines being used in 4/4s (solidly Ford from 1955 apart from a dalliance with Fiat in the early eighties). Was this an upgrade by the owner? I can see the sense as the Z18XER has more oumph that than the Duratex (1800) or Zetec (1600) engines as provided by the faxtory. But both the Ford engines are easily tweaked and any Morgan dealer will know what they're dealing with.
