Tilton also includes a few...
Tilton also includes a few different size pressure plates to compensate for the wear on the discs and floaters. A graph and wear gauge are provided with the clutch to determine when a new pressure plate is needed.The drive hub is a unique piece that is patented by Tilton. Since the discs are made of carbon, the hub is a floater design rather than a rivet-style set-up.
Taking advantage of lightweight material is a necessity especially in four-cylinder applications. Many have tinkered with various ceramics and iron materials to improve clutch engagement and these efforts have been successful to some degree. The downfall of this approach is unavoidable; it is simply how a limited amount of surface area effects the heat resistance property of the clutch. Excess heat sacrifices holding power. Tilton addressed two fronts with its clutch-using twin discs to increase surface area and using exotic materials for added heat resistance. Tilton decided to use a lightweight carbon material for the following reasons; it's lighter than most other materials and has better wear properties, the clutch cover and pressure plate are made of aluminum, adding to the lightness as well as increasing the strength of the clutch assembly. Unlike most flywheels the Tilton chrome-moly flywheel has no friction contact patch for the drive plates (discs) to ride on. The unit relies on three floater plates to make contact with the number two-drive plate rather having the carbon contact the chrome moly surface. This not only improves the wear properties of the clutch but it also saves time when servicing the clutch. The starter ring gear is also machined into the unit and added perforations aid in cooling of the clutch while reducing weight. The 4140-chrome-moly flywheel is also heat-treated to endure extreme temperatures.
At each step of development the weight of the carbon composite material, the titanium clutch cover and all other materials were considered.
Tilton's Carbon/Carbon clutches for Hondas are available in 185mm diameter which is much smaller than a typical single-disc unit which measures in at 221mm. The smaller size has an effect on an engine's moment of inertia in comparison to an OEM unit. The rotating mass is narrowed down to the center of the crank which allows the engine rev up more freely. The lighter load that the engine has to rotate is not only less than the OEM unit because of the lightweight material used, its moment of inertia is changed due to remaining weight of the clutch being so close to the center of the crank. The weight of a single-disc clutch and OEM flywheel on a B-series Honda is 29.8 lbs. The total weight of the Tilton unit is 12.6 lbs-the difference in these figures make it plain to see the advantages of the Tilton set-up.
Friction material and friction area are also critical concerns when dealing with high-horsepower applications. In the past, and present, different types of material have been used to transfer horsepower to the ground. Along with material concerns the size of clutch disc contact points (i.e. four puck, six puck and full face discs) are important factors. With the Carbon/Carbon unit Tilton relied on carbon composite to provide the necessary clamping force to transfer stratospheric power to the ground. What's different from most single-disc units is the use of a full carbon on carbon contact surface. With most single-disc units, the difference in disc material versus flywheel and pressure plate material tends to distort and cause uneven wear to all the parts. Since the Tilton's floaters and discs are constructed of carbon they share the same heat properties and, in turn, generate an even wear pattern while providing plenty of hook and book force. Even the chrome-moly flywheel and pressure plate becomes a non-friction contact patch due to the two additional floater plates the discs ride on.
The three floater discs are...
The three floater discs are also of carbon construction making the unit a carbon-on-carbon design. This use of common material also increases the unit's heat resistance properties which is advantageous to performance and durability.