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Tilton 7.25" OT-II Metallic Racing Clutches (Cover Mount Ring-Gears)

Tilton 7.25'' OT-II  Metallic Racing Clutches (Cover Mount Ring-Gears)
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Price:  $692.75(Exc. 7% Sales Tax - GA only)
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Part Number:  66-803HG

Tilton

Installation Instructions (PDF)
Installation Drawing (PDF)

Tiltonís 7.25″ OT-II metallic racing clutch covers, for use with cover mounted ring-gears. These triple plate clutches are designed primarily for road racing, circle track, open wheel and formula applications, Tiltonís 7.25″ OT-II metallic racing clutches offer the low moment-of-inertia, high torque capacity and reliability necessary for the most demanding racing applications. These features have made metallic clutches the most common clutch type used in road racing and circle track racing. Metallic clutches are not recommended for street use. These features make Tiltonís 7.25″ OT-II metallic racing clutches popular in the applications below:

  • Road Racing
  • Circle Track
  • Open Wheel
  • Track Racing
  • Street Circuit
  • Open, one-piece clutch cover design. Provides lower operating temperature, higher strength and minimized deflection for quick shifting
  • Various diaphragm spring rate options, roviding a wide range of torque capacities and release loads to tune the clutch for the application
  • Chrome vanadium diaphragm springs and an engineered pressure plate geometry. Provides a high clamp load-to-wear ratio, low release load and quick shifting
  • High-strength steel pressure and floater plates. 0.104″ thick friction discs. Provides excellent wear resistance and withstands elevated temperatures
  • Hardened steel thrust buttons provide a smooth and durable surface for pressure and floater plates
  • Dynamic spin balanced and individually inspected for proper assembly and balance, initialed by the QC personnel
  • Tilton uses a color system for indicating the angle and weight of the clutch spring, which has an effect on release load and torque capacity for the clutch. The exact values for each color vary depending on the type of clutch, so be sure to check the charts below to find exact measurements.


    3 Plate Clutch Specifications:

    Weight**:  9.9 lbs / 5.4 kg
    M.O.I.**:  87.6 lb-in2 / .0258 kg-m2

    SPRING COLORTORQUE CAPACITY (LB-FT/NM)RELEASE LOAD* (LBS/DAN)PRESSURE PLATE (RATIO)
    WHITE400/544400/180HIGH
    WHITE480/652400/180ULTRA-HIGH
    BUFF720/979480/211HIGH
    BUFF855/1163480/211ULTRA-HIGH
    ORANGE840/1142560/247HIGH
    ORANGE1005/1367560/427ULTRA-HIGH
    GRAY1020/1387680/299HIGH
    GRAY1230/1673680/299ULTRA-HIGH
    DOUBLE GRAY1140/1550760/334HIGH
    DOUBLE GRAY1365/1856760/334ULTRA-HIGH
    TRIPLE GRAY1245/1693800/352HIGH

     

     

     

     

     

     

     

     

     

     

     

     

     


     

    * Values listed are typical for release bearings with the recommended 44mm contact diameter. Larger contact diameters will increase release load.

    ** Weight and M.O.I. include pressure plate, carbon floater plates, carbon discs and steel hub, and may vary based on your particular spline.

     

    Tilton offer two different styles of every clutch configuration: one designed to be compatible with a step-type flywheel and another for pot-type (“no-step”) flywheels. Step flywheels have a .100″ step for contact with the friction material of the clutch, so clutches made for this application will have a .100″ height difference between the bottom friction disc and the end of the clutch cover legs (the mounting points). Pot flywheels don’t have this step, so the friction disc and clutch cover legs will be flush on clutches designed for them.

    Tilton’s metallic clutches are available with either a High Ratio or Ultra-High Ratio pressure plate. High Ratio pressure plates offer high clamp load over a wide wear range, while Ultra-High Ratio pressure plates provide 20% more clamp load and diaphragm spring travel (modulation). As seen on the graph below, the clamp load (or torque capacity) of the High Ratio pressure plate is relatively flat until .030″ (0.76mm) of wear; Ultra-High Ratio pressure plates offer a higher initial clamp load at a faster wear rate.



    • Standard pressure plate ratio for Tilton metallic clutches
    • Short release travel for quick engagement and faster shifting
    • Flat clamp load curve for longest wear range

    • 20% more release travel than High Ratio for improved modulation
    • 20% more clamp load than High Ratio for higher peak torque capacity
    • Clamp load drops more quickly with wear than High Ratio