There were 7 production Engines sizes for the Mini: 850, 970, 997, 998, 1071, 1098, 1275. Nearly all of them however (with the exception of 850 & 1098) came in different states of tune from the factory.

For power information on the individual engines, please visit the Performance specs page.

Buying a modified engine can be a bad idea. Make sure that all of the work was done professionally, and a Rolling road report is always a good idea.