I have just got some updated information concerning Engines and Powertrains:
The new Prince Engine will be built at Douvrin according to my list!
2006 is when production starts, but there will still be some old Tritec engines built into 2007
These are the SOP (start of production) dates for the various engines, gearboxes and model versions. The Toyota 75hp diesel engines continue into R56 (there is also no higher powered diesel listed

)
2006 1.6l 140hp 6-speed R50
2007 1.6l 110hp 6-speed R50
2007 1.6l 110hp CVT R50
2007 1.4l 75hp 5-speed R56
2007 1.4l 90hp 6-speed R56
2007 1.4l 90hp CVT R56
2007 1.6l 110hp 6-speed R56
2007 1.6l 110hp CVT R56
2007 1.6l 140hp 6-speed R56
2007 1.6l 170hp 6-speed R56
All of these Petrol engined variants would also appear in a Mini Roadster as of End 2008
Also interesting is that all engines apart from the 75hp have the 6-speed gearbox.
All of the petrol engines are DOHC
I don't have torque figures for any of the Petrol engines (probably because they are not yet know)
And, of course, the 170hp engine is Turbocharged
That pretty much summarises the list, looks like 2006 will be the bad year to buy a Mini unless end of life discounts are plentiful
