Bilstein 5-way EVO: new state-of-the-art motorsport shock absorber
“It would be weird if it were faster”
Flashback to January 2019. A 24-hour race in Dubai. Black Falcon and BILSTEIN are testing a completely new shock absorber development for the first time on a circuit. The prototype of a new 5-way shock absorber proves to be fast, surprisingly fast on the desert course. Martin Flick, Head of Motorsport at BILSTEIN, recalls: “It was an incredibly positive confirmation that the shock absorber was so fast right from the start. We hadn’t expected this in the form we were in yet, and it was already very strong. If he’d been faster, it would have been scary too.”
A few months and many more tests later the brand new and “5-way EVO” motorsport shock absorber comes onto the market. The new shock absorber is available in two versions: The BILSTEIN EVO RX 5-way for use in rally and rallycross sports and the BILSTEIN 5-way EVO RT for circuit and GT sport.
The BILSTEIN 5-way EVO complements our motorsport shock absorber range and rounds off the range above the MDS 4-way shock absorber. As a particularly cleanly designed state-of-the-art motorsport shock absorber, the latest development from BILSTEIN impresses with maximum performance and durability.
“The big difference between the MDS 4-way shock absorber and the 5-way EVO is that the 5-way EVO can also adjust the rebound in the high-speed range,” explains Martin Flick. That’s not the only difference. “The shock absorber also works completely differently: While the previous MDS 4-way shock absorber adjusts the bottom valve, and thus causes a lot of hysteresis due to pressure build-up in the entire oil volume of the shock absorber, the pressure stage of the EVO shock absorber is much more rigidly supported.”
The brand new shock absorber achieves this by working with smaller oil volumes in areas where pressure changes occur. According to Martin Flick, this makes him the physically better damper. The motorsport expert adds: “Both the MDS 4-way shock absorber and the EVO RT 5-way shock absorber have blow-off valves that absorb peak loads. In the new BILSTEIN 5-way EVO, however, it is much more effective. The increase can be reduced by about 50 percent. The blow-off valve in the MDS 4-way shock absorber can only absorb around 10 to 20 percent of the force.”
Particularly with regard to durability, the new high-tech shock absorber benefits from the test work on particularly demanding tracks. Martin Flick: “We put most of the development for the valves into the EVO RX 5-way shock absorbers and worked together with Team GCK from the World Rally Cross Championship. Which also makes sense, because the forces and pressures in rallycross are much greater than in GT. We are talking about a factor of four to six! This is an advantage for the valve development: On the one hand, as far as durability is concerned, the motto is what works in EVO RX will also work in the EVO RT. But also in terms of grip and frequency capability, the requirements in rallycross are very high.”
BILSTEIN engineers also attached particular importance to ease of operation and adjustment options. The BILSTEIN 5-way EVO leaves nothing to be desired with a total of up to 100,000 setting options. The 10 clicks of the 5-way EVO change the driving behaviour noticeably and almost without interaction of rebound and compression stage. This simplifies handling and enables clearly reproducible driving and test results for a perfectly tuned setup.
In addition, the patented colour and number coding makes counting clicks superfluous and saves valuable time in the pit lane. All setup variants can be defined with a numeric code and called up in racing mode. Additional security is provided by the haptic click feedback during Adjustment.
Anton Marklund and Guerlain Chicherit show how well the new BILSTEIN 5-way EVO already performs under competitive conditions in the World Rally Cross Championship. The Renault Mégane RS RX of the French team are regularly among the fastest cars in the field.