current family sedans use inline 6 cylinder engines (4.0L capacity) that have 182kw (that's the base model). There is also a V8 option (5.4L capacity) that sports 220kw standard. Then there are sports variants:
- Inline 6 cylinder turbo (240kw, but much, much more potential)
- Semi-worked V8 (260kw)
- Range-topping performance V8 (290kw).
I'm sure plenty of other people will elaborate with times and such. I hope it's a start anyway =)
BTW: Looks like you've got some car there! UK's fastest, eh? Impressive!