Well Simon, when I discovered that my engine didn't take the ST 220 oil filter and took the Jag/Zetec filter I asked the factory , because the 220 filter is bigger. They told me that the base engine was Jaguar. I might still have the response - I'll have a look later!
The oil filter is Jaguar, as is the starter motor and the gearbox. The engine is Mondeo
The original prototype (now owned by Tim Harrison) used the Lincoln/Jaguar engine
All Production S1 used the Mondeo engine
Simon @ SiFab.co.uk