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How To Degree DOHC Camshafts

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    How To Degree DOHC Camshafts

    Pics will be up soon.



    This is what you will need:

    - Pencil
    - Paper
    - Degree Wheel (The bigger the more accurate the readings)
    - Pointer (can be made from a coat hanger)
    - Piston Stop (Get the kind that goes in the spark plug hole)
    - Dial Indicator (You can use one or more than one)
    - 19mm Socket
    - Ratchet or Breaker Bar for Socket
    - Adjustable Cam Gears

    How to do it:

    The process of camshaft degreeing almost always starts with the adjustable cam gears set at the zero position and the camshafts installed to match factory specifications. I also recommend that you degree the cam with
    the lash set at 0.000.”


    1. Install the Degree wheel onto the crankshaft. Try to get it as centered as possible. Don't worry if you can't get it perfect, as you will be moving it later.


    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. Rotate the crank to get the # 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.


    4. Turn the crankshaft opposite the running rotation (clockwise) approximately 15-20 degrees. Install a piston stop into the # 1 spark plug hole. Note: A dial gauge can also be used.


    5. Continue to turn the engine in the same direction (clockwise) 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.
    Last edited by djcaz_aom; 01-09-2015, 06:02 PM.

    Black Housing DIY 1991 Wagon Morimoto Retrofit
    JDM One-Piece Headlight Lens Repair

    #2
    6. Now, rotate the engine in the opposite direction (running rotation,
    ; counter-clockwise) 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. Loosen the degree wheel and adjust it so it will read 0º TDC at the pointer. Don’t rotate the crankshaft to do this! Now, repeat steps 5 & 6 to verify the piston is at the true top dead center. Once it is, move on.


    8. Now, it’s time to locate the lobe center line relative to TDC. Attach a dial indicator on the top of the cylinder head. You might have to get creative here unless you bought a kit made for your motor. Set the tip to contact the top of the no 1-cylinder VALVE SPRING RETAINER. The rocker arm does not work. 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 (counter-clockwise) until a reading on the dial gauge of .050" 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 (counter-clockwise) past maximum lift. The valve will now return to its close position. Make a note of the degree wheel reading when the indicator reads 0.050″ on the return side
    Last edited by djcaz_aom; 01-09-2015, 05:55 PM.

    Black Housing DIY 1991 Wagon Morimoto Retrofit
    JDM One-Piece Headlight Lens Repair

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      #3
      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 closing reading was 43. Now add 43 to 180 = 223, subtract 4 = 219 divide by 2 = 109.5. Lobe center is 109.5 degrees.

      To adjust, loosen the bolts on your cam gears and rotate the crankshaft until it is at the degree specified.

      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
      Last edited by djcaz_aom; 01-09-2015, 06:00 PM.

      Black Housing DIY 1991 Wagon Morimoto Retrofit
      JDM One-Piece Headlight Lens Repair

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