Hi I emailed any inquiry to Intrax regarding suspension solutions and thought I would share the outcome. Hello Kevin, Thanks for your interest in our products. Underneath I’ll explain all the systems we have available (in Europe the Pulsar is called Sunni). For fast road use all our systems are suitable. This is because the shocks are custom build. The setting, springs, length of shocks etc. all are calculated to your planned use and wishes. This means that a full 4-way “race” system can be built by us as I highly adjustable street system. The most popular systems for street use are our RSA and 1K2 upside down systems. This because the Nissan Pulsar GTiR has a Macpherson suspension system for the front and rear. With our upside down construction we add lots of installation stiffness (less flex) in the Macpherson construction which already gives a better handling and stability without hardening the suspension. If there are any questions left after this mail, don’t hesitate to call or mail us. As you probably already know all our shocks are all custom made, we adjust the springs and setting for the purpose they will be used for but the price doesn’t change. For the trackday use we do advice our 1K2 and 4-way system the setting will be made that it can also be used for fast street use. For what purpose will your car be used (street, trackday, race, rally etc. or a combination)? Fast road use What type and size tire will the car drive on? What size rim do you use? Any other change (compared to standard) on the car that can influence the handling of the car (weight, power, roll cage etc)? I want to point out our unique ARC® system which can be seen as the icing on the cake. With this system a softer spring can be used with all its benefits (more traction, more grip, easier to drive, less tire rear, in case of street use more comfort etc.) without the disadvantages of the softer spring (more body roll/pitch, collapsing suspension etc.) The 1K2 and RSA are externally adjustable in damping and adjustable in height. Intrax chooses one knob for the damping adjustment. With this one knob you can set different damping settings. When you adjust the knob, both rebound and compression will be adjusted in the correct damping force. This unique system makes it very easy to find the correct setup for your driving style and road conditions. Finally the damping system is equipped with a heat device (thermostat) to insure damping force will stay constant under all operation temperatures. RS Like the RSA “regular set up but without damping adjustment and no thermostat. RSA “regular” set up This shock will get a custom made setting adjusted to the wishes of the driver. It has a spindle of 22mm which gives extra installation stiffness (less flex) in the front suspension. The adjuster for the damping is mounted at the top and of course these shocks are height adjustable.