[advantage20]

Are we actually sure that the M Performance versions of future UKL-based models will be designated as M35i?

There has been a heavy tendency at BMW to round off its engine designations in the upwards direction (28 to 30, 35 to 40, 45 to 50...), obviously in order to follow the gradual output increase, but also I assume because round numbers make a more solid visual and mental impact and are just easier to remember and therefore are preferrable from a marketing standpoint.

If we look at current models which will eventually all become UKL-based (1 Series, X1...), their highest non-M Performance version is designated 25i and rated at around 230ps. For instance there is no more 130i as the next step above 125i is directly the M140i.

Since there seemingly won't be any more UKL-based models designated 30i, isn't it possible that the M Performance versions will take that blank spot and be labeled M30i instead of M35i? Of course, if we assume it won't be M40i in order to not mess up with the 6 cylinder non-UKL based growing M Performance lineup (X3 and X4 M40i, future M340i and M440i...), which I think is quite an easy assumption. Not that M35i absolutely has to be zeroed off to M30i in order to be consistent with the other M Performance designations (M40*, M50*, M60*...), but it doesn't seem totally impossible either, since there will be at least half a numerical step backwards anyway (current non-UKL M140i ---> future UKL M135i) already violating the above mentioned custom according to which same level designations aren't supposed to be moving downwards (though they can justify this with the move from 6 to 4 cylinders).

However BMW seems to want to keep a numerical difference of 10 between the M Performance version and the strongest non-M Performance version (330i ---> M340i, 540d ---> M550d...), so if the strongest regular versions of the UKL-based models are deemed to peak at 25i then the case is quite strong that the M Performance versions will likely have to be designated M35i in the end by lack of a better option.