Tilton 7.25&5.5 Carbon Clutches (98-1300) - Manual (Page 2)

Cover Assembly
Pressure Ring/Plate
First Floater [^]
First Drive Plate [X]
Second Floater [^^]
Drive Hub
Second Drive Plate [XX]
Third Floater [^^^]
FIREW
AL
L
9. Set the pedal stop. Table 1 lists a theoretical maximum master cylinder stroke. There is
another more preferred method. Place the car on jack stands. With the engine off, and the
transmission in first gear, slowly depress the clutch pedal while having another person trying
to rotate a drive wheel or driveshaft until the point where the clutch releases. Measured at
the footpad, give the pedal an additional 1/4" (6 mm) of travel and set the pedal stop there
(Diagram 1).
MaIntenance
1. Thicker replacement pressure plates, in .010" (.25mm) increments, are available to compen-
sate for clutch wear (5.5" clutch: Table 2, 7.25" clutch: Table 3). Even though the clutch is
usually capable of of withstanding .040" (1.02mm) or more of wear before clutch slippage
will occur, it is recommended that pressure plates be changed at .020" (.51mm) increments
to keep clutch near peak clamp load and torque capacity. If maintaining consistent pedal
action for the driver is important, it is recommended that pressure plates be changed at
.010" (.25mm) intervals. The most accurate method is to measure the thickness of the
individual plates with a micrometer (Diagram 3), not calipers, to the nearest .0005" (.01mm)
and compare them to the dimensions of the plates listed on the build sheet supplied with
the clutch. Once you determine how much total wear there is in the carbon stack, select
the appropriate pressure plate thickness to install. Do not install a pressure plate that is too
thick. Otherwise, the stack height underneath the clutch cover will be too tall and will cause
release problems and/or damage the clutch.
2. Check the clearance between drive hub fingers and the slots in the driven plates (Diagram 4).
The slots must not be more than .025" (.64 mm) wider than the drive hub’s fingers. This is best
checked with a feeler gauge. Premature wear of the slots is usually an indication of input shaft
misalignment with respect to the crankshaft.
3. Check hub float. With the clutch installed on the flywheel the drive hub should be able to
float at least .010" (.25 mm) on the input shaft. Once the axial float disappears the clutch will
start to slip.
4. Check for signs of excessive heat. A blue-colored hub is a sign of high temperatures from a
clutch having been slipped excessively. High temperatures can cause the diaphragm spring
to lose clamp load. Send the assembly back to Tilton for inspection if damage is suspected.
5. Increased wear at the release bearing contact area is a sign of a heavy left foot or a bearing
that needs to be replaced. Many clutches have been lost to the failure of an inexpensive
bearing that was run one race too many.
Measure at least three different places in the
middle of the wear area, and take the average
of all measurements.
Diagram 4
Diagram 1
Diagram 3
Diagram 5
Diagram 2
5.5" and 7.25"