Nice document. Notice the production has been done predominantly with CAD. This means the pictures in the manual are the 3D digital engineering designs/"drawings" used by BMW adapted for this guide. Pretty cool and likely also a time/cost savings for BMW.
The things I found most interesting:
- Differences to M5 engine include: oil system, VANOS (low pressure), weight savings, MSS60 engine control vs. MSS65, double roller cam chain vs. single (most of which we already knew)
- Lightweight carpet
- Key dependent M-drive settings (for "certain" settings) - cool!
- Mirrors became larger to comply with future legislation
- Seat shape and foam is different in EU compared to US
- Pistons contain a "running in coating" containing tin and are identical to E60 M5 pistons
- Low pressure VANOS saved 8.4 kg compared to M5 system
- One piece radiator in the M3 compared to two piece in the M5
- Document seems a bit contradictory about the transmission. In one place it says the transmission is based on the US 6MT in the M5 but when it lists part numbers is show it identical to the 335i. I think, as I predicted all along all three are almost identical with the M3 even sharing the 335i ratios.
- 4kg reduced weight in the clutch compared to the M5
- Driveshaft cv joints from M5 (nicely over-rated for the lower torque in the M3)
- Completely different front end geometry compared to 335i
- Interesting that they published the detail on EDC and the graphs of damping force vs. piston speed and the dynamic range of adjustment obtainable by EDC.