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Cam degree or camshaft degreeing is the process of adjusting the lobe center of the cam to a
predetermine crankshaft position. Because this is basically done by means of a protractor and in degrees
represented by the prortractor the expression of camshaft degree, cam degree or degreeing
cams stuck.
 Adjustable cam gears help in the process of adjusting the
camshafts so that it opens and closes at the correct time. Adjustable cam gear allows the engine tuner or
engine builder to move the crank whilst the cams remain stationary or vice verse. Camshaft degree insures
that maximum lift correspond to a desired crank position. The center line or the point on the cam where
maximum lift occurs is known as lobe center.
Setting the cams to zero on the cam gear means absolutely nothing and might even in some cases be harmful.
Lobe centers on the HKS 264's are 110 for the inlet cam and 103 for the exhaust cam. Adjusting your cams too these
specs will most probably bring them very close to their maximum designed performance . A lobe center of 110 on the
inlet cam means that maximum valve opening will be at 110º ATDC and 103 on the exhaust will mean that maximum valve
lift will be at 103º BTDC
How to degree cams.
1. Use a pencil, paper and arithmetic for this procedure, to keep track of the results.
2. Fashion a rigid pointer from stiff wire or an old coat hanger and attach it to the engine block. This pointer
locates the degrees on the degree wheel.
3. With a degree wheel installed on the crankshaft, rotate the crank to get the no 1- piston at TDC and check to
ensure that the valves are fully closed then adjust the pointer to zero (0º TDC) on the degree wheel. (free printable degree
wheel)
4. Turn the crankshaft opposite the running rotation approximately 15-20 degrees. Install a piston stop on the top
of the engine block fastened in place by two head bolts or in the case of overhead cams install the piston stop
into the spark plug holes. Note: A dial gauge can also be used.
5. Continue to turn the engine in the same direction until the piston comes back up and just touches the piston
stop. Make a note of the exact number on the degree wheel that the pointer is on.
6. Rotate the engine in the other direction (running rotation) until the piston comes back up and touches the
piston stop. Again note the number where the pointer is.
7. Remove the piston stop and rotate the crankshaft to the midpoint of the two marks. At this point the piston is
at the true top dead center. Loosen the degree wheel and adjust it so it will read 0º TDC at the pointer. Don't
rotate the crankshaft to do this!
8. Now, it's time to locate the lobe centerline relative to TDC. Attach a dial indicator on the top of the engine
block. Set the tip to contact the top of the no 1-cylinder inlet valve shim/bucket. Check to make sure that the
indicator plunger is parallel to the valve stem. NOTE - any variance in an angle will produce geometric errors in
the lift readings.
9. Rotate the engine in the normal direction of rotation until a reading on the dial gauge of 0.040? lift is
reached. (Valve will start to open) Mark the dial gauge and make a note of the reading on the degree wheel.
10. Continue to turn the engine in the normal direction past maximum lift. The valve will now return to its close
position. Make a note of the degree wheel reading when the indicator reads 0.040" on the return side
11. Now add the larger of the two readings that you noted on the degree wheel to 180 subtract the smaller number
and then divide the answer by two. Your answer will indicate the lobe center of the cam. Example: open reading was
4 and close reading was 43. Now add 43 to 180 = 223, subtract 4 = 219 divide by 2 = 109.5. Lobe center is 109.5
degrees.
12. Continue to move the cam on the adjustable cam gear and redo steps 10 to 12 until the required lobe center is
achieved.
13. Now do the same for the exhaust cam
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