http://f80.bimmerpost.com/forums/sho...d.php?t=892746


50% unique parts compared to F30/F32
Bi-turbo inline 6 cylinder (S55)
430 HP (approximately) and "far beyond" 369+ LB-FT (500 Nm)
Higher than 7500 RPM redline
Under 3,306 lb (1500kg) weight
Fuel consumption & emissions reduced by 25%
CFRP drive shaft, roof, trunk (M4), front strut brace, roof bow
6 speed manual standard, 7 speed DCT optional
Active M Differential
Forged Crankshaft
Optional Adaptive M suspension
Electric power steering
50:50 weight distribution


SPECS


ENGINE•

3.0L inline 6 cylinder engine (S55) with two mono-scroll turbochargers◦3,027 cc (compare to 2,979 cc of N55)
◦89.6mm bore / 80mm stroke over-square (compare to 84mm bore / 89.6mm stroke under-square of N55)
◦Derived from N55 engine
◦Direct Injection
◦VALVETRONIC
◦Double-VANOS
◦closed-decked crankcase (4.4 lbs / 2kg lighter)
◦twin-wire arc-spray coating (instead of liners) in cylinder bores reduce engine weight
◦20 lbs lighter than V8 S65 engine (from E90/E92 M3)

•430 HP (approximately) from around 5000-7300 RPM
•"far beyond" 369+ LB-FT (500 Nm) from under 2000 RPM to over 5000 RPM
•See Dyno Chart
•Slightly above 7500 RPM redline

TURBOS•
Two Mitsubishi mono-scroll turbochargers
•18.1 PSI / 1.25 BAR max peak
•Pre-tensioned in Sport and Sport+ modes (keep spinning at a high rate of speed even after throttle lift-off, for ultra quick response - more details)
•Impulse charging for optimized responsiveness
•Flow-enhanced manifolds
•Electric wastegate actuator

COOLING•
Double-flow oil recirculation pumps
•Turbocharger suction system
•Main radiator plus additional radiators for the high- and low-temperature circuits, turbocharger and transmission
•Large indirect intercooler (sits atop engine, necessitating hood bulge)
•Low-weight magnesium oil sump (2.2 lbs / 1kg lighter)
•Temperature-stabilizing electric water pump


WEIGHT•
Under 3,306 lb (1500kg) weight ◦this figure is without driver and with 90% fuel
◦BMW clarifies that "the new model is now around 80 kilograms [176 lbs] lighter than a comparably equipped predecessor model"
◦compare to E46 M3 at ~3,400 lb curb weight
◦compare to E92 M3 at ~3,600 lb curb weight
◦compare to C63 AMG at ~3,900 lb curb weight
◦compare to RS5 at ~4,000 lb curb weight

•~ 7.68 lb/hp power to weight ◦compare to E92 M3 at 8.7
◦compare to C63 AMG at 8.7
◦compare to RS5 at 9.0
◦compare to E46 M3 at 10.25

•Fuel consumption and emissions reduction of 25%

CARBON FIBER CONSTRUCTION / BODY•

CFRP drive shaft (tested for speeds up to 205 MPH)◦40% weight savings over previous M3
◦increased stiffness
◦reduced rotating mass for better acceleration and throttle response

•CFRP roof for both M3 and M4◦saves 11 pounds (5kg) on M3
◦saves more than 13.2 pounds (6kg) on M4

•CFRP roof bow
•Carbon fiber trunk for M4 (11 pounds (5kg) weight savings)
•CFRP front strut brace standard (weighs just 3.3 pounds (1.5 kg))
•Front fenders and hood made from aluminum

TRANSMISSION•
Standard 6 speed manual transmission ◦automatic throttle blips on downshift
◦more compact and quieter than predecessor E90/E92 M3 6 speed
◦26.4 pounds (12kg) lighter
◦carbon fiber friction linings in synchroniser rings
◦dry sump lubrication

•Optional 7 speed M DCT (double clutch transmission) with launch control
•Active M Differential with constantly variable locking (a la M5/M6), from 0 to 100 percent
•Forged crankshaft

STEERING•
Entirely new electric power steering (EPS) unit, built by ZF
•Specially tuned for M3/M4
•Servotronic function electronically adjusts the level of steering assistance
•Three modes: Comfort, Sport, Sport+
•Will not compensate for understeer, oversteer, coarse road surface. Motor will not help unwind the steering wheel and it will self-center by by natural forces

SUSPENSION / CHASSIS•
Optional EDC Adaptive M suspension (with Comfort, Sport, Sport+ modes)
•CFRP front strut brace
•Double-joint spring strut front axle (saves 11 pounds)
•New five-link rear axle made from forged aluminum (saves 6.6 pounds)
•Aluminum suspension
•Aluminium stiffening plate
•Rear axle subframe fixed directly to body (bolted joints between the axle subframe and the body sills, without use of elastic rubber elements).

WHEELS / BRAKES•
18 and 19 inch options will be available
•Lightweight forged wheels standard
•Staggered tire sizes - 255/35 ZR front and 275/35 ZR rear
•Prototypes fitted with Michelin Pilot Sport tires, but other tire brands will be certified as well
•M compound brakes standard (in blue)◦four piston front / two piston rear

•M carbon ceramic brakes optional (in gold)◦six piston front / four piston rear


EXHAUST•
Exhaust features electrically controlled flaps just before rear silencer to minimize exhaust back-pressure as well as giving precise feedback on engine load.◦When closed, flow is forced into and laterally across the silencer; when open, flow is more directly through the narrow part of the silencer.

•Catalysts with metal substrate (less restrictive than ceramic)
•Exhaust always exits all four tail pipes

AERO•
50:50 weight distribution
•Air Curtain
•M gills with integrated Air Breather behind front wheels

MISC•
The M3/M4 standalone components amounts to roughly 50 per cent. This includes body, chassis and powertrain components.
•Llithium-ion starter battery under consideration.
•M3 and M4 to be introduced together (at Detroit NAIAS 2014 in January).
•M3 and M4 developed with help of BMW race car drivers Bruno Spengler and Timo Glock's participation in extensive testing and set- up runs on the Nürburgring-Nordschleife circuit, focusing on assessment of the cars’ suspension, tyres and all elements of the powertrain.