The KONI Special (red) has been engineered to maximize the ride comfort with good handling performance for each vehicle application. The KONI Sport (yellow) typically starts at a higher initial valving baseline to give a sportier feel and work on vehicles with higher performance parts. In some instances, KONI will only offer a Special or Sport valving and not both. Some modern cars come from the factory with higher tech suspension systems and wheel/tire packages so they would move directly into the Sport range, however they are still valved to give a comfortable ride with very good handling capabilities.
This is a difficult question to answer because every KONI application is developed for that specific vehicle to get the best handling characteristics. In general, most factory shocks are under damped for optimized handling so KONI engineers select firmer valvings. Unfortunately factory shocks are generally chosen for financial reasons rather than performance so lower technology, cheaper shocks are standard. In some instances, a factory shock may have good characteristics in some parts of the working range but need some help in other parts and there are even a few instances where the KONI engineers found better handling by softening the factory units.
There is no single best adjustment setting for your KONIs because every driver has different preferences for comfort, performance, performance modifications and roads to drive on. For most vehicles, we suggest that new KONIs be installed in the full soft position. (the standard setting right out of the box) to take advantage of the balance of ride comfort and handling designed by the KONI ride development engineers. If the car has performance upgrades (springs, wheel/tire packages, etc.) or the driver wants the car a bit more aggressive, most people find the optimum setting in the 1/2 to one full turn from the full soft range. Over the extended life of the damper or if the driver wants a specific firm handling characteristic, the dampers can be adjusted up higher. Very rarely will KONI ever need to be adjusted to the full firm setting.
One of the great advantages of KONI adjustable shocks is that there is no specific spring for matching optimum performance. Instead you can adjust your KONIs to match your springs. Most performance springs have a higher spring rate than the vehicle's original springs. Since the shock controls the motion of the spring, increased spring rates require more rebound damping for control and that is one of the reasons why KONIs are rebound adjustable (and some are double adjustable). Using higher rate springs with OE or soft shocks will very quickly overcome and wear out the shocks. The KONI adjustment range is typically about 100% (twice as firm at the full firm settings at the full soft setting) to allow for proper damping of OE springs and high rate performance springs.
KONIs are designed to fit standard height cars and can work with lowered cars as long as they don't bottom out internally and become damaged. Unlike some shocks, KONIs are not position sensitive so they will work properly anywhere in their stroke range providing they are not bottoming or topping out. Different vehicle suspension designs have different stroke travels but a good rule of thumb is that most vehicles can be lowered acceptably about 1 1/2 inches, beyond that the possibility of bottoming increases rapidly although some longer stroke cars can go lower. Most vehicles are equipped with bump stops to keep the shocks and springs from bottoming out. When lowering a vehicle be sure to reuse your bump stops as they are cheap insurance to avoid bottoming damage. Remember also that severely lowered vehicles typically also have a negative effect on suspension geometry, ride quality and handling, and tire and suspension part wear.
There are basically three types of shock absorber designs: mono-tube high pressure gas, twin-tube low pressure gas and twin tube hydraulic (non-gas). Each of these designs has a certain ride and performance characteristics that can enhance the performance of a vehicle and KONI is the only company that makes three designs. KONI ride development engineers evaluate each new vehicle and can decide which shock design would best apply to that vehicle. Some cars respond to mono-tubes, some like gas pressurized and others don't. Most shock companies utilize only one or two of these style because it is less expensive for manufacturing but are therefore limited in design capability and function.
There are many coil-over sleeve systems on the market but the key is to get ones that will fit the KONI damper properly. Most of these are built to fit over a large number of aftermarket shock absorber brands but this means many will not really fit well. KONI is unique in that some applications feature an adjustable spring seat mounted on a circlip on the shock body. This circlip design is extremely strong when it is loaded properly and the circlip is captured so that it cannot be forced open. However if the mounting on the circlip is unevenly loaded or not properly captured allowing the circlip to increase in diameter from load or impact, you have a potentially dangerous situation where damage could occur. With proper installation and loading, the circlip system allows for great strength and ride height adjustability at the same time. Additionally, when selecting and installing your coil-over system, care should be taken to avoid allowing the springs to coil bind (compressing the spring down to a solid state) during usage as this can risk bottoming and damage. A proper length bump rubber should be used to keep the spring from coil binding and the shocks from bottoming internally. You should contact the dealer or the manufacture of the coil-over system and get any necessary adapter rings necessary to mount the sleeve system to the KONI.
Whenever possible, we try to have the application be externally adjustable so that they can be easily adjusted on the car. In some cases this is not possible due to design constraints imposed by the vehicle. Some cars have no way to physically access an adjuster on the car or have mounts that prohibit an adjustable shock. In these cases, the shocks are still adjustable but must be removed from the car to do so.
The dampers in Threaded Suspension Kits are based on KONI Sport shocks but have been made specifically for the elements of the kits. Depending on the applications, some have different maximum or minimum lengths and valvings to specifically match the springs and lowering goals of the kits.
The KONI North America warranty is to the original purchaser against defects in materials or workmanship for as long as you own that car (registered for street use) during the applicable warranty period in your country. The warranty does not cover damage to the parts caused by misuse, misapplication, installation, motorsports, etc. and does also not include mounting bushings.
The warranty involves replacement. When replacement is no longer possible the warranty involves repair. When repair is no longer possible the warranty involves a refund.
Always get in touch with the point of purchase (with a copy of the purchase and vehicle registration) or, when point of purchase is no longer existent, the KONI distributor in your country.
Shocks and struts are similar in that they both damp (slow down) the vehicles motion. The key difference of a strut vs. a shock is that a shock only controls the cars motion while a strut is a locating member of the suspension. What this means is that if you remove a shock the spindle or axle will still be completely attached to the vehicle. If you remove a strut the spindle or axle will be able to move outside of its normal motion. Shocks and struts may or may not have a spring mounted to them either. It is often assumed that any damper with a spring is a strut, this is not the case.
Contact your KONI wholesaler. They will determine what opportunities are available to you.