H&R's Cup Kits provide springs and dampers engineered to work together at low ride height, even using a shortened body in certain applications. Cup Kits allow a useful increase in spring rate, whereas Sport spring rates are normally limited by the performance of the stock damper. Also, the elimination of "lazy coils" that normally do no work saves weight and cost.
H&R's Cup Kits provide springs and dampers engineered to work together at low ride height,
Testing A System
This is the fun part. The road H&R uses for much of its testing begins just a few hundred meters from the factory's front gate. That not only saves time, it allows H&R to use cars off new car dealers' lots, because they don't put a whole lot of kilometers on the clock. The road has fast sweepers, super-tight slow kinks, on- and off-camber curves and bumps on straights and in the turns. It has everything our favorite roads have and just about any challenge anyone is ever likely to encounter.
In H&R's installation and fitting area, there is a large bin of 10kg sandbags used to load the vehicle for testing. It is loaded to its maximum weight rating, then taken out and pounded over the same road, taking corners with bumps at speed.
There are two drivers; one is a track day nut and drives fast. At the end of the road, they trade places and the ride specialist drives back. For the most sporting models, H&R also tests on tracks such as the Nrburgring, usually Uwe Alzen and his brother. They are considered two of the fastest Porsche drivers in Germany: When they say the setup is good enough, it's nearly perfect.
Approving The System
Once H&R's engineers are satisfied, the system goes for TV approval. The TV officer examines the engineering documentation, checks sample parts for compliance with the specification and, finally, road tests the car himself. He does the same testing the H&R technicians do but generally drives even harder. He is a picky, hard-to-satisfy guy. This process has led to H&R's engineers developing a working relationship with the local TV office based on familiarity and mutual respect. H&R's engineers feel that TV requirements are a good thing. "Everybody has an idea, but not every idea is a good one." TV tries to keep the not-so-good ideas from becoming a problem for unsuspecting customers.
H&R's damper technicians assemble smaller damper production runs on site, as well as rebuilding them to test valving configurations during development. Monotube dampers are filled by this special machine that largely automates the process.
H&R's damper technicians assemble smaller damper production runs on site, as well as rebui
H&R has built TV-approved coilovers for more than a decade, with dampers manufactured to its own specifications, tuned by its own engineers. H&R's damper range has grown to include PCS coilovers with adjustable dampers, Cup Kits and Performance Dampers. In addition to developing dampers and valving at H&R's headquarters, its engineers build small series of dampers and do competition service and custom work. Clearly, there has been a large quantity of damper knowledge and experience built up.
Walter Wirtz, H&R's manager of suspension development, says that every damper company has its own philosophy. european car has spoken with many different companies. We could name two companies with excellent reputations and products that work well, whose engineers vary significantly in their opinions of what is a good design. That's not to say anything works well. Roland Graef, head of H&R's North American operations, often compares suspension tuning to music. When everything is in harmony, the car works well. There is, however, more than one tune that pleases people. This writer has never heard H&R hit a bad note.
Herr Wirtz uses and recommends John Dixon's "Shock Absorber Handbook" for those looking to learn really useful information about suspension tuning. The volume is a publication in English of the Society of Automotive Engineers, a U.S.-based organization. Be warned, however, that the book's high math content was enough to cause Dave Coleman, Sport Compact Car's Engineering Editor, to put it back on his shelf and leave it there for several years.