Degreeing a Cam

Discussion in 'High Performance Modifications' started by Scaleytail, Sep 20, 2020.

  1. Scaleytail

    Scaleytail Veteran Member

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    Recently changed out Camshaft. Did not degree the Camshaft, put everything back together exactly as it came off. No vacuum idle timing is at 4 BTDC and fully advanced 36 degrees is an inch away from the timing tab. The balancer is keyed, so TDC is true. It’s running pretty good, but I can’t wrap my head around the timing marks being off. Any thoughts?
     
  2. 70lt1z28

    70lt1z28 Veteran Member Gold Member

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    Original stock damper? If so, that 40+ year old rubber can take a set and the outer ring slip. Take the damper off and compare the timing mark with a new one and see if it lines up.
     
  3. Scaleytail

    Scaleytail Veteran Member

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    It’s a three year old engine. The balancer is keyed, soI don’t think that’s off.Lined every thing up. Just can’t wrap my head around my timing set up seems to be 8 degrees off. It runs very well ...but this isn’t right or I’m missing something.
     
  4. 1980RS

    1980RS Veteran Member

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    No vacuum or low vacuum may be a result of the cam. What did you have for a cam and what did you go too?
     
  5. Scaleytail

    Scaleytail Veteran Member

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    Went from 221/226 @50 .528/.536 110 to .234/.234@50 .576/.576 111. Best vacuum is now a lil over 11.
     
  6. COPO

    COPO Veteran Member Lifetime Gold Member

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    Truly find your marks.
     
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  7. biker

    biker Veteran Member

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    I think he meant he checked the timing with no vac advance hooked up.
     
  8. Lowend

    Lowend Administrator. .a car, a man, a maraca. Staff Member Lifetime Gold Member

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    Are you sure the wires are right on the distributor cap. I've seen a lot of very experienced techs swap wires and get some odd results
     
  9. Scaleytail

    Scaleytail Veteran Member

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    Timing is done with the vacuum advance removed and hose plugged.Will recheck wires but the car runs pretty good. Gonna verify TDC tomorrow. Something fishy is gonna on...my timing indicates 4 BTDC-max advance is 46 thinking its actually 14 BTDC and max timing of 36 ....missing 10 degrees
     
  10. biker

    biker Veteran Member

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    That is odd. Reading 10 too low at idle and 10 too high at max total timing? Timing light messed up? Dial back digital on a weird setting?

    I agree that your actual timing must close to perfect. My cam is similar, and will not idle at 4" btdc
     
    Last edited: Sep 21, 2020

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