Wednesday 27th April 2016

Koeningsegg to Qoros in one step

Koenigsegg-backed Freevalve cam-less tech previewed in Chinese-market Qoros

---

Camshafts have been around since, well, since the four-stroke engine was invented really. That could be about to change though, because Chinese carmaker Qoros has revealed the cam-less Qamfree concept car at the Beijing Motor Show.

The cam-less system has been developed by Swedish company, FreeValve AB, a sister company of Koenigsegg. It uses, wait for it, pneumatic-hydraulic-electric-actuator technology (PHEA) on each valve to perform the opening and closing routine. This means the engine management system has full variable control of each valve individually. Advantages are claimed to be more power combined with reduced fuel consumption, emissions and weight.

So why is it better? The cam lobes on a conventional mechanical camshaft are fixed, which is a major compromise. Ideally an engine needs one profile for a low speed trundle to the shops but a completely different profile to run flat out on a track day. Variable cam timing has helped, as has Honda's VTEC cam-lobe-switching system and BMW's Valvetronic system which mainly control valve lift, but they're still a compromise. FreeValve combines variable valve lift with variable valve timing, all in one.

The nearest to a production fully variable valvetrain to date is Fiat's MultiAir system. Instead of the cam opening the valves directly, it generates hydraulic pressure which can be released by solenoids to control the valve lift and to an extent, the timing. But the FreeValve system goes one step further and gets rid of the camshaft altogether. Hydraulic and pneumatic pressure is piped to an actuator atop each valve and an integral solenoid used to control the opening and closing.

FreeValve claims a 12-17 per cent reduction in fuel consumption under laboratory conditions compared to a state of the art 2.0-litre direct inject engine with variable camshaft timing. The company has been hard at work on this concept, which is in its sixth generation, since 2000. But it's not the first to go cam-less.

Similar concepts have been shown by BMW, Fiat and Lotus Engineering over the years, to name a few. In those cases, the valves were opened by electro-magnetic solenoids which proved too expensive, too slow and consumed too much power. Now though, FreeValve, Koenigsegg and Qoros could be on to something.

Freevalve promo vid

Freevalve from Freevalve on Vimeo.  

[Sources: Freevalve AB]

[British Beef]

Sounds complicated, therefore cost and unreliability are likely to increase.

Not an issue on an ultra rare and expensive supercar, unlikely to feature on the next Ford Fiesta.