GMS SLT (SuperLightTrack) forged wheels are designed with a purpose of winning races. They are superlight, they are strong and they provide additional brake cooling effect to the brake rotors. The wheels are made out of T6-6061 forging and come in a shape of state of art monoblock, 10 spoke Y-design, hollowed forged wheel.
Wheels come in recommended size 17x7.5 ET28 @ 6.9kg and 18x9.0 ET35 7.4kg for raw, unpainted wheels. The wheel load rating of a single wheel is 620kg (for this dimension). Custom sizing (width and ET), custom RAL colors (heavy duty powder coating) and aluminum CNC billet center caps are available as an option, so lots of personalized options are available for those who like to stand out of the crowd. PCD is standard 4C, 5 x 98mm.
The fabrication of the wheel starts with forging about 40kg of T6-6061 alloy, forming it in to a forged, monoblock wheel blank. Forging is done to gain better material properties (less porosity, better structural density), which means we can use about 25% percent less material, which is where we save the weight, without compromising the wheel strength. This procedure is then followed by CNC lathe turning to get the rough shape and get a wheel with a weight of about 20kg's. Forging blanks are outsourced while the next step is where our job begins.
The wheel fabrication on our side starts by CAD designing of the wheel (Wheel diameter, ET, PCD, CB, the cooling effect on the rotors and finally the looks), followed by FEA optimization, and finally, the CNC process.
Precision 5-axis CNC machining gets the wheel in to a final shape and removes all the unnecessary weight. For ultimate weight reduction, we use another separate CNC process, to hollow the spokes and save the weight, while not compromising the wheel's strength too much. After that, the wheels are checked for roundness and balanced to -/+ 20g. Next step is hand deburring of CNC hard to reach sharp edges, followed by preparation of the wheels for the final step - powder coating in RAL color of your choice.
According to CAD FEA simulation we have a wheel load rating of about 620kg, before excessively fatiguing the wheel. Long analyze in short. These wheels are designed to withstand more than 2G of lateral forces on 4C on the track - easily. However, even though a forged wheel is considerably stronger than cast or flow formed wheel of same weight, it is still a wearable item. Wheels don’t last forever. Wheels are designed with a triangular concept - weight, strength and longevity. A wheel can be made strong and heavy to last forever, or it can be made light and less strong, that will last less. You have to consider that trade off for any brand and any type of the wheel. Wheels are fatigued items, it doesn’t matter if a wheel is cast, flow formed or forged, they will all fail, eventually. So as with any ultralightweight, we also recommend a periodic inspection for potential stress cracks on these wheels. Stress cracks caused by material fatigue, most commonly apper at the back of the wheel, especially near the hub and the spokes attaching to the barrel. Carefully look for hairline cracks after each tracking seasion. In case of any irregularities, replace the wheels immediately. Safety first! Track use only!
Standard wheels on stock. Wheels in custom sizing will be delivered in 90-120 days upon placing an order and receiving a full payment.
GMS SLT Forged wheels 17" and 18"
- Superlight wheels (17x7.5 ET28 @ 6.9kg and 18x9.0 ET35 @ 7.4kg)
- PCD 5 x 98mm
- 620 kg wheel load rating (capable to withstand over 2G of lateral forces)
- Reduced unsprung weight
- Increased brake cooling
- T6-6061 forged monoblock design
- 5-Axis CNC machined hollowed spokes
- CNC billet aluminum center caps optional
- Custom colors optional
- Custom sizing optional (width and ET)
- Sold as a set (4x wheels)
- Fits all Alfa Romeo 4C Coupe and Spider models