In the meantime the SX-3 is available in the fourth evolution stage (series 4). The consistent development is shown through the very good race results the SX-3 chassis has achieved during the last years. Special attention has been paid to the compatibility of new parts in order to give drivers the possibility to upgrade their SX-3 chassis any time.
The extraordinary characteristics of the SX-3 chassis have been achieved through well thought construction with innovative detail solutions unique precision and use of high quality material. A-arms and many other parts are made of high-strength alloy with high resistance and low weight. The good quality of the parts is appreciated by the H.A.R.M. drivers worldwide.
The SX3 series 4 is equipped with changeable carbon fibre stiffeners on both sides what allows further adjustment. Through the three different stiffeners 2,0 mm – 3,0 mm torsion of the chassis can be influenced. The chassis can be adapted to different driving behaviours grip-conditions and race tracks. The rear suspension of the SX-3 series 4 offers adjustment possibilities in order to influence the roll center through different positions of the a-arms.
Through the changes of the series 4 the SX-3 is one of the most effective competition chassis on the market and offers drivers all kind of adaptations with regard to driving behaviour and race tracks. 

An adjustable alloy front suspension which enables adjustment of a-arms is mounted as standard as well as the carbon fibre reinforcement.
The front upper a-arms offer better crash safety through missing turn buckles. Adjustment of camber is facilitated by means of spacers. A-arms front lower are equipped with adjustable stabilizer bar. Toe width at the front axle has been optimized. Through the design of the a-arms the adjustment range of caster (up to 20 degree) has been increased.

With the chassis construction of the SX3 series 4 (2008) the philosophy – easy handling with maximum traction and steering performance – of the successful SX3 (2007) has been still optimized.
Basis of the SX-3 chassis is a double chassis construction. The advantages of this construction have  proved their reliability over years and have been now even advanced and improved with the series 4.
The new carbon fibre side stiffeners are available in three different sizes in order to be able to adapt the stiffness of the chassis to different track conditions. Changes in this section of the chassis have a considerable effect on the driving behaviour of the car. On slippery tracks the 2 mm stiffeners should be mounted in order to get additional traction. The 3 mm bar leads to maximum stiffness and provides a distortion free chassis with extreme grip conditions. The 2,5 mm size can be mounted on almost every track.
The brake servos are mounted next to the steering servo in the servo tray in order to facilitate quick changes of the bars. This enables best maintenance possibilities.

The rear fixation point of the a-arms rear lower is not adjustable what simplifies setup adjustment. The same high quality ball insertion as with #1511333 is used. The fixation point in the front is still adjustable by means of turn buckles. Therefore the stability and the stiffness of the a-arm has been improved essentially. The a-arms allow a change of wheel base of up to 4 mm. The stabilizer is mounted directly on the a-arms and hardness can be adjusted.

As already mentioned the rear suspension of the SX-3 series 4 offers a lot of adjustment possibilities without loss of easy maintenance. As most of the aluminium parts of the SX-3 chassis also the damper support rear is made of high strength aluminium.

The SX-3 chassis are strictly delivered completely pre-mounted. All screws are fixed with Loctite. The chassis delivered are all measured and adjusted with a basic setup. This enables the driver to get first impression and to gain experience with the new chassis right away without having problems through building or setup mistakes. First of all, of course the radio has to be build in and ride height needs to be checked. The ride height can be changed easily through adjustment of the damper springs.

• pre-mounted chassis, all screws fixed with Loctite
• front bumper
• CNC milled chassis made of high-strength aluminium
• adjustable alloy front bulkhead
• alloy a-arms front
• adjustable ball stabilizer front
• alloy axle hub front, light
• alloy damper plate front
• damper quick release
• precision oil damper
• carbon fibre stiffener 3 mm
• carbon fibre servo plate 3,5 mm
• alloy a-arms rear
• adjustable stabilizer rear
• alloy differential, manual adjustable
• alloy differential mounts
• alloy damper plate rear
• alloy reinforcement a-arm rear
• double rear support including brace
• ball drive
• alloy axle hub rear, light
• 3-hole motor mount, self-centering
• 23 cc motor Zenaoh G230 RC
• race air box set made by Mielke
• alternatively “Big-Power”, “Steel-Power” or “Hurrican” pipe made by Mielke
• high-tech hydraulic brake front and rear (alternatively mechanical disk brake)
• basic set-up

• two-part differential mounts, set
• Hydraulic brakes front and rear with epoxy discs

• Remote Control System
• 1 servo for steering
• 2 servos for brake and throttle
• 1 receiver battery
• 1 body