Performance gains are possible by knowing how shocks will affect chassismovement and weight transfer. It is important to know our shock ratesand how different rates produce desired effects. Proper shockmainten-ance helps us to be sure that parts are working and our shockrates have not changed.
In today's racing world, we have pre-built shocks available with any number of combinations of disk designs and valving. Some types of designs provide the ability to adjust shock rates quickly at the race track. With all of these choices, we have what we need to choose the exact rate of compression and rebound necessary for a particular set of conditions. This can either be an advantage or the proverbial "enough rope to hang..." syndrome. The more we learn, the better we can make decisions regarding shock selection.
More and more, racers are being educated in all aspects of chassis tuning and they want to know more about shock technology. The more we know about each of these subjects, the less fear we have. It is what we don't know that we fear the most.
The information presented here is intended as a guide to help you understand the basic principles of shock technology and the art of track tuning with shocks. Exact rates for the shocks you need for your car will depend on how your car is constructed, set up, and driven, as well as factors such as weight distribution and race track characteristics.
We would really like to give you the exact shock values that will make your car as fast as it can be, but that would be impossible due to the many variables. Those variables are why you must work with your particular car and not follow what others are doing. Each car is a little different than the others and each driver has his/her own style of driving.
Part One dealt with the basic construction of the racing shock. We learned that the two strokes of the shock, rebound and compression, are looked at separately and perform functions related to different areas of track tuning. If we deal with rebound and compression separately, we need to be able to tune each independently. There are also different designs of shock pistons including the linear design and the digressive design. Again, we are able to achieve varying results by utilizing all of the variables of shock design.
For some situations, we would use split valve shocks. Split-valving means we have different rates of resistance for rebound and compression because we need to tune each movement a little differently than the other. We can also rate the two movements differently for each corner of the car to further tune the setup.
If we want, we can buy (at a greater expense) shocks that have external adjustments for rebound, compression, or both (called double adjustable). That way, we can experiment with different shock rates without removing them from the car. Regardless of how we arrive at different shock rates, we do need to know beforehand what we are looking for and how to get there.
Shock companies provide a system of numbers or letters to reference the rates of rebound and compression. Most of these companies try to provide a cross-reference so that their numbering system can be compared to the other systems used by competing shock brands. The ultimate match between shock brands is not exact due to differences in design of the valving and the fact that companies will rate shocks at a different shaft speed.