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  1. #1
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    Default Big Twin Evo Timing Cup off 180 degrees

    I switched out my cam (Andres ev27) on my 93 evo. When I went to static time with the Eletronic ignition (s&s Hi-4n) I noticed the timing cup was pointed the other way(TDC).Click image for larger version. 

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ID:	109207 The Red line is where the slot part of the timing cup is pointing and the yellow is where it needs to be. You can see here that I aligned the Cam to the pinion and Breather Gear. Click image for larger version. 

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ID:	109208 Kinda confused. I have installed these before. Everything looked stock when I was in there.

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    Doing the cam timing and doing the ignition timing are two completely independent operations.

    Turn the motor over (forward) until you have the front cylinder on its compression stroke and then proceed with your ignition timing.

    Jim

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    Hi Jim,
    When I move the motor over to have the front cylinder on compression stroke. Piston up and valves closed with the TDC mark showing. My Timing Cup looks like that in the picture. If that makes sense.

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    You are in overlap then, not the compression stroke.

    Jim

    Edit: To be clearer, I should have said that you are on the exhaust stroke. Turn the motor one full turn and you will be on the compression stroke.
    Last edited by JBinNC; 09-26-2022 at 5:34 PM.

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    Jim
    With it on the Compression stroke I should still be able to see the TDC line in the timing hole? Also what should my pushrods be looking like? front intake up? rear cylinder on overlap?

    Thanks in advance

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    Yes, TDC mark will be visible on compression or exhaust stroke. (720 crank degrees or 2 turns for the full four cycles)

    The front intake valve will open and close, and both valves will be closed on the compression stroke. Intake valve closes at the start of the compression stroke.

    Front cylinder on compression, rear cylinder is on overlap, yes.

    Jim

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