Andy was talking about a V8 last year, but I think there was a serious impediment regarding the weight taken by the front end.
Maybe a trany engine might be more practical.
Rover V8 - aluminium - light weight
Transit engine (Ford Pinto) - cast iron - bloody heavy
new Ford DOHC / Zetec - aluminium - as Rover
That argument is cojones.
.... as a footnote to this, I recall a kit car web site somewhere (either Westfield or Dax Rush I think) with a list of engine weights comparing the Rover to the Pinto as being similar (if not lighter in the case of a 3.5 Rover).