Audi claims the GFRP springs, which were developed in collaboration with an Italian supplier, are 40 per cent lighter than standard steel springs. Where a steel spring may weigh 2.7kg, a GFRP spring with the same properties would weigh approximately 1.6kg, saving roughly 4.4kg from the weight of “an upper mid-size model” – the kind of vehicle under which Audi says the new suspension will debut.
Audi AG technical development head Dr Ulrich Hackenberg said the GFRP springs save weight at a crucial location in the chassis system.
“We are therefore making driving more precise and enhancing vibrational comfort,” Hackenberg said.
The GFRP springs are light green, their fibre strands are thicker than the wire of a steel spring, and they have a larger overall diameter with a lower number of coils. The core of the spring consists of long glass fibres twisted together and impregnated with epoxy resin.
Audi says GFRP does not corrode, even after stone chipping, and is resistant to chemicals such as wheel cleaners. GFRP spring production also requires significantly less energy than the production of steel springs.
Audi has not confirmed which “upper mid-size model” will be the first to benefit from the technology at this stage, though given its high cost and high-performance characteristics, one possibility is a debut in the Audi RS6 Plus that leaked online yesterday.
Renault claimed to be the first brand to use composite springs in a production car last month when it launched the hardcore Megane RS275 Trophy-R. The track-honed Renault Sport model’s innovative lightweight front springs are produced by Allevard.