To the M brand faithful, the decision to replace the iconic straight six engine in the M3, was nothing short of heresy.

To the devout BMW patron, this was a dark day that would cast a shadow on the brand for all time.

Well, it appears that the head honchos in the M division were listening.

The 2015 M3/4 see the return to a straight six power-plant. The M3 is the 4 door variant and the M4 is the 2 door, why they changed the nomenclature is as perplexing as the decision to leave tradition behind and use an 8 cylinder.

The inline six has an output of 425 hp and 406 lb-ft. The 3.0L engine uses twin turbo’s and can be matched to either a 6 speed manual, or a 7 speed DCT transmission.

For those who care, the 0-100km/h(60mph) times are 4.6 for the manual and 4.4 for the DCT(Double clutch transmission).

The 2015 M4 Cabriolet, should be in dealerships now with prices around $84500.00 Canadian. Just in time to enjoy the fall colours and the last of the decent weather.

The other advantage to the drop-top version will be unfiltered access to the iconic straight six soundtrack.

Other standard mechanical bits include the Active M rear differential and electro-mechanical steering. The latter promises precision and direct feedback, but only time and the M brand loyal will tell if this new tech is fully accepted.

Other M goodies include the standard M compound brakes, or the optional gold calipered ceramic brakes for those who frequent track days, launch control, three mode suspension, steering and transmission settings, allowing you to enjoy your car in any situation.

To grant access to the new M4 true capabilities the engineers utilised much aluminum and carbon fibre reinforced plastic to shed weight in key locations.

As an example, the CFRP drive-shaft is produced as a single piece unit. This eliminates the need for a center support bearing.

As a result the new single piece weighs 40% less, and it is more rigid providing smoother power transfer and a better response to throttle input, you have to love new technology.

The interior is classic BMW, clean, comfortable and luxurious. M badges adorn everything form the gear lever to the door sills. Leather wraps most every body contact point.

Its just a nice place to be.