The BMW M3 CRT (Carbon Racing Technology) is a limited-edition high-performance sports car based on the BMW M3 saloon and it utilises carbon fibre reinforced plastic (CFRP) to minimise weight.
The use of CFRP in the construction of the car helps it achieve a weight-to-power ratio of 3.5 kg per horsepower.
CFRP process
The process used to manufacture the bonnet for the BMW M3 CRT has been developed for the BMW i3 and i8 models, which are scheduled to enter volume production in 2013. These will feature a CFRP passenger cell. BMW believes this manufacturing process opens up considerable potential for increased use of CFRP in series-produced cars.
The BMW M3 CRT bonnet is made from two CFRP mouldings encasing an aramid honeycomb core material. This construction imbues the bonnet with the strength of a conventional steel bonnet, but at roughly 25% of its weight. The weight saving over the aluminium bonnet of the standard BMW M3 saloon is around 50%.
For the car’s driver and front passenger bucket seats the CFRP encloses a recycled-paper honeycomb, with a carbon composite layer (made using conventional production technology) added to visible areas.
CFRP is also used to make both the rear spoiler of the BMW M3 CRT and an air-channelling element integrated into its front apron.
Lightweight design
The BMW M3 CRT is the latest in the company's line of exclusive high-performance sports cars optimised with the help of lightweight design.
This lineage stretches back to the BMW 3.0 CSL of the 1970s and reached another high point in 2002 with the BMW M3 CSL.
BMW M GmbH also broke new ground with the use of CFRP in series-produced vehicles; like the BMW M6 produced up to 2010, the current BMW M3 Coupé comes as standard with a roof made from CFRP.
Equipped as standard, the BMW M3 CRT has an unladen weight of 1580 kg, which is around 45 kg less than that of the standard BMW M3 saloon. BMW notes that if you take into account the equipment on board the weight saving is more like 70 kg.
The BMW M3 CRT will be produced by the BMW M GmbH factory in a limited run of 67 units.
This is the second small-series, high-performance M3 off-shoot to be designed for the race track but registered for the road. It follows the BMW M3 GTS, of which 135 were produced.
