Over the past two days we ‘ve learned quite a lot about the 1M from Dr Kay Segler and BMW NA M Brand Manager Matthew Russell. For starters yes that is a Z4 35is N54B30TO (aka “n54hp “) engine under the hood. While we had heard that there were various internal changes done by M. We can now confirm that there are no physical changes to the engine.
As you heard in our interview with Matt Russell the Z4 35is has a N54 variant that was itself tweaked by the engineers at M. Specifically they have created two throttle maps (via the M button) and in turn created the most raucous N54 variant yet (based on how it sounded while revving at the show). From the lighter flywheel to the enhanced software and everything in between M went through the N54 thoroughly in creating the Z4 35is. Tolerances are tighter and the soul of the engine has been enhanced.
Dr. Segler was adamant that M had taken the soul of this N54 and turned up several notches to create something that has a different character than the Z4 35is.
Also interesting was Dr. Segler ‘s comments on the development of the car. The time-frame that M had to work within was impacted by of all things the weather. The fact that most of the development took place at the ‘Ring (an M tradition) meant that M only had from April to October of this year to engineer and then sort the car. But what you end up with is “Pure M ” has Dr. Segler calls it. What does that mean? In a quantitative way it means the 1M can do four laps on the ‘Ring generally unfazed (ie without much brake fade etc).
The manual transmission has been something often overlooked when talking about the 1M. Yes the lack of DCT has been referenced constantly in forums and even was the NAIAS floor this week. But what about the actual 6 speed in the car? We can now confirm that it is the same 6 speed found in the 135i with a E46 ZHP shift knob. The clutch however is the same item as in the
Z4 35is 335is (due to needing to support the 369 ft lbs of torque on overboost).
Speaking of transplants one of the more interesting things we learned this week is that M not only transplanted the entire suspension and braking system but the sub-frame of the M3. It ‘s easy to compare this car to a E30 or even an E46 M3. But the more you look at the components the more the 1M looks eerily similar to the E92 M3 on paper.
Finally the question of brake ducts. Yes the pair giant holes in the front bumper are not brake ducts as you might expect. They are actually need to bring air to the oil and water coolers. But M hasn ‘t forgotten about the brakes. Instead M has designed paths cleared under the chin to ensure plenty of fresh air reaches the brakes.[nggallery id=51]