25 September 2013

BMW M3 & M4 - Juicy Technical Details Announced

BMW has announced the much awaited details of its forthcoming M-car, the M3 and M4. Originated as an M3, the model has to be split due to BMW new naming convention which segregate the 4 door and 2 door coupe version with different numerics. We already know how BMW 3 Series sedan and 4 Series coupe look like (refer to the BMW M4 Concept above) so let's just dwell on the technological grand force of the new M cars.

In powertrain department, the previous M3 is powered by S65 engine which displaces 3,999cc and kicks out 414hp at dizzying 8,300rpm and 400Nm@3,900rpm, breathing a naturally-aspirated system. The V8 mill is capable of thrusting the M3 to century sprint in 4 seconds flat. Moving on to the next stage, BMW is banking their M3/M4 with new S55B30. Apart from displacing less at 3.0L, and reverting back to venerable straight-six configuration, the new lump features twin turbocharger to boost the power to 430hp and pulling out more than 500Nm. Consistent with the force-fed nature, the power and torque is maintain over a fat range.

S55B30 engine adopt close deck engine architecture for an increase in rigidity accommodating the high cylinder pressure resulted from a boosted engine. Cylinder walls features twin-wire arc spray coating instead of conventional liners. The cranktrain system is also lightened to reduce the rotating mass and thus enhance engine responsiveness. The crankshaft is a forged unit which blend ultra rigidity and allow optimization in rotating mass and the conrod has been suitably beefed up too.

The new BMW M3 and M4 will features a host of weight saving technology, in pursuit of less than 1,500kg of kerb weight. This include carbon fibre roof and carbon fibre propeller shaft. The body panels too is subject to weight diet exercise. The lighter roof (which also reduce the weight away from the C.o.G) is further supported by CFRP trunk lid panel. The weight saving activity extends to suspension system too, whereby the control arm, wheel carrier and axle subframe are made of aluminum. Overall weight reduction from existing car is around 80kg.

The increase in power and the reduction in weight will gives higher power density. Apart from fulfilling the handling mantra of an M-car with improved steering precision, on-limit adjustability, enhanced agility and outstanding directional stability, the new BMW M3/M4 is supplied with track-ready cooling system and oil supply system. The thermal management will ensure optimal cooling whether you are blasting around the track or trundling around the city, and this include indirect intercooler to cool the intake air, additional radiators from high and low temperature water circuit, turbocharger and engine oil. Additional electric coolant pump cools the turbo bearing when car is stationary.

The oil system features the sump made of magnesium with special baffle plate to contain the oil under strong 'g'. Also designed for an extreme dynamic envelope is the oil extraction pump and oil return system to maintain an uninterrupted oil circulation.

BMW M3 and M4 comes in two transmission of choice. The first up is the 6 speed manual box. Innovation surrounding it include carbon friction lining in syncroniser rings, dry sump lubrication and have throttle blips control function. The gearbox is not only more compact, but also 12kg lighter then the existing unit. The second option is M Dual Clutch transmission with 7 forward ratios and comes with Launch Control. It is claimed to have an ultra fast gearchange that minimise power interruption. Another system making an appearance is the Active M Differentials. It uses an electric actuator to vary the locking effect in real time continuously.

Pheww. More salivating photos can be found after the jump which detailed out the engine and chassis components. 

The CFRP parts on BMW M3 and M4

The Drivetrain Unit

The exhaust manifold which fed into the mono-scroll turbocharger

Magnesium oil sump

The long forged crankshaft on the in-line six

The cutaway of the mono-scroll turbocharger unit

The suspension layout

No comments: