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  1. #11
    Moderator beerdart's Avatar
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    How does the CB alignment affect ignition timing? Shifting the encoder wheel two bolt holes is 120deg where is the 9deg difference come from?

    Quote Originally Posted by Sea Dood View Post
    If you put a 2006+ crank in an earlier engine by pulling the pin and moving the encoder CCW two flywheel bolts, the ignition timing ends up being retarded 9 degrees. Retarding 9 degrees at idle would only affect RPM. But the 4-TEC system adjusts airflow through the idle bypass valve to keep RPM at 1800. At high RPM, the ignition system is dynamic; it pushes the timing until it finds knock and backs it off a few degrees. It just might not be able to push it enough to maximize power in certain ranges. And mid-range probably does suffer.

    Unless the 2007 crank I have was manufactured wrong! Anyone else have a late crank they can inspect and report back?


  2. #12
    Shifting the encoder wheel two bolts is 120 degrees like you say. But if you look carefully, when you shift the encoder wheel two holes on a 2006+ crank, ythe encoder wheel doesn't end up in the same spot; it is two holes + one tooth relative to the early crank. There are 40 teeth on the CB gear. Each tooth is therefore 9 degrees.

    Put it another way, the entire set of 6 holes is shifted 9 degrees (one tooth) between early and late cranks. Look at the number of teeth difference to the timing mark to the nearby hole; it is three teeth on early cranks, two on later ones.

  3. #13
    Moderator beerdart's Avatar
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    Counter balance alignment has nothing to do with ignition timing. With the crank pinned the encoder wheel is rotated 120deg no more no less.

  4. #14
    Quote Originally Posted by beerdart View Post
    Counter balance alignment has nothing to do with ignition timing. With the crank pinned the encoder wheel is rotated 120deg no more no less.
    I agree that CB alignment has nothing to do with it; you have to stop thinking that way.

    Think of it this way;

    1. Picture that the CB alignment mark is always at 3 o'clock, or 90 degrees relative to TDC when crank is pinned. This is true on either early or late.

    2. The encoder wheel gets it's relation to TDC from the bolt holes, not the timing mark.

    3. But if the timing mark is at 90 degrees, and the relation of the bolt holes is 9 degrees (one tooth) different between early and late, then the encoder wheel is 9 degrees off between early and late (in relation to the bolt holes)

    4. Therefore, the ignition timing difference between early and late cranks is not 120 degrees (two bolt holes), it is 129 degrees (two holes and one tooth)

    That is, of course, if the 2007 crank I have sitting here is not fukked up, which it could be, LOL. Need others to post pictures verifying this is true.

  5. #15
    Here's closeup photos so you can see the difference more easily.

    Click image for larger version. 

Name:	2004 crank.jpg 
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ID:	232179Click image for larger version. 

Name:	2007 crank.jpg 
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ID:	232180

  6. #16
    Just got looking at it more closely, and I noticed something; it is not exactly one tooth shift. It is slightly less than one full tooth shift. So it looks like it is about 7 degrees difference instead of 9.

  7. #17
    Moderator beerdart's Avatar
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    I here what you are saying as long as the CB mark is 90deg with the crank pinned. So it appears that in 06 when they changed the location of the crank trigger it was shifted 127 deg. So the the crank swap from early to late is not as easy as shifting the encoder 120deg. I wounder if the encoder wheels are different between the years.

    Quote Originally Posted by Sea Dood View Post
    I agree that CB alignment has nothing to do with it; you have to stop thinking that way.

    Think of it this way;

    1. Picture that the CB alignment mark is always at 3 o'clock, or 90 degrees relative to TDC when crank is pinned. This is true on either early or late.

    2. The encoder wheel gets it's relation to TDC from the bolt holes, not the timing mark.

    3. But if the timing mark is at 90 degrees, and the relation of the bolt holes is 9 degrees (one tooth) different between early and late, then the encoder wheel is 9 degrees off between early and late (in relation to the bolt holes)

    4. Therefore, the ignition timing difference between early and late cranks is not 120 degrees (two bolt holes), it is 129 degrees (two holes and one tooth)

    That is, of course, if the 2007 crank I have sitting here is not fukked up, which it could be, LOL. Need others to post pictures verifying this is true.


    ---------- Post added at 11:50 AM ---------- Previous post was at 11:45 AM ----------

    Just checked they changed encode wheel parts numbers in 06.

  8. #18
    R88ory RXP's Avatar
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    [QUOTE=beerdart;1648752]I here what you are saying as long as the CB mark is 90deg with the crank pinned. So it appears that in 06 when they changed the location of the crank trigger it was shifted 127 deg. So the the crank swap from early to late is not as easy as shifting the encoder 120deg. I wounder if the encoder wheels are different between the years.

    [COLOR="Silver"]

    ---------- Post added at 11:50 AM ---------- Previous post was at 11:45 AM ----------


    Very soon I hope to confirm weather it makes a difference, I will have to check the static ignition timing on my Haltech, I know what it should be for a 04 engine, I dont yet know what it actualy is for my engine, 04 with 06+ crank.

    If this is the case there are going to be a few people out there with missing performance, the stock setup can only go as high as the timing map, it can pull from there depending on knock but it wont go above the timing map to "replace" the missing timing. This is my understanding of the stock timing setup.

    R88



    Cheers R88

  9. #19
    speedskixp's Avatar
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    Good info on this thread. thanks for sharing.

  10. #20
    Moderator beerdart's Avatar
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    It appears that the cam chain drive gear has 19 teeth so 18deg per tooth so 129deg on the CB gear would keep the cam timing correct. Does that sound logical??


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