This news comes from this week's Autoexpress:
“Bosses at MINI are playing it cool on the future of the popular supermini's engine range – but pictures in the current issue of Auto Express magazine will send a shiver down their spines. We've scooped two prototypes putting hot new powerplants through their paces.
Although they don't sport the facelifted front first revealed in issue 779, the cars do have a mysterious bulge on the bonnet. Insiders at the company have confirmed that an engine development project is well underway. And while the changes will be hidden from the eye, they are expected to revolutionise the way the model drives.
The BMW-developed MINI currently uses a 1.6-litre four-cylinder unit developed jointly with Chrysler. In the past, the South American-built engine, which is available with 100, 115 and 163bhp power outputs, has been criticised for lacking refinement and low rev torque. So a new 1.6-litre – to be assembled at the Hams Hall plant in the Midlands – will replace it next year. Not only will it offer better performance and smoothness, but also improved fuel economy. Base versions, to be fitted in the MINI One, are tipped to offer around 110bhp, while a new 130bhp unit is planned for the Cooper. However, future motors for the Cooper S are still under discussion.
We've learned there's support for a new 2.0-litre with around 180bhp, plus a similarly powerful 1.6 turbo. The three engines will feature in the forthcoming Cabriolet. Prices for cars with the new units will be revealed closer to launch. Dan Strong “
From what I can gather these figures are a bit off of BMW internal forecasts. In fact you can see the entire model development in this previous post. From MINI's internal forcast it would seem the Cooper will be around the 140hp mark with a 6-speed (most likely a Getrag) and the Cooper S will have a turbocharged 170hp engine – both 1.6L in size.
Regardless of hp numbers I think I can say with some confidence that AutoExpress is not referring to the 2005 model year when they mention the roll out dates of these engines. Again from the information I've seen the Cooper version comes out first (in the current R50) in late 2005 as a 2006. Then it gets tricky, again according to the supposed timeline, the new MINI (codenamed the R56) comes out in late 2006 as a 2007 model. That's when the MCS will join the MC with the new engine – it's output around 170hp.
For more information on this engine you can check out these posts from last year: New MINI Engine Caught Testing and The MINI Gets a Prince.