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Thread: how the f*%# do i get cam timing correct?

  1. #1
    Moderator DustinsDuster's Avatar
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    how the f*%# do i get cam timing correct?

    i'm running BC 272 cams in my truck, and it seems no matter what i do, the cam gears end up about a half tooth out when i run a straight edge across them. with the straight edge lined up on the outside notches on the cams, and both the inner notches are about an 1/8" raised off the straight edge. move the exhaust cam gear one tooth forward and the inner notches come up under the straight edge.

    anyone else ever have to deal with this? how did you resolve it? the truck seems to run well now(mid 12's at 108-110), but i'm starting to wonder if the cams being slightly out of time is why my tune is so wacky. -41% global fuel with stock Evo 8 560cc injectors, and my ignition timing is backed off as far as ECMLink will let me at 3000-4000rpm and i still start seeing knock. am i stuck getting adjustable cam gears to correct the timing, or does someone here have a eureka idea that'll keep me from spending the money?



    Tango 'til they're sore

  2. #2
    IAF Team Member Clinical's Avatar
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    I know I posted on your FB post, but just posting to say that mine are the EXACT same way from the sounds of it.
    I retimed it about 20 times probably before I just said screw it and threw it all back together. I also have BC 272s in my car.
    Even have all the timing tools and such and followed everything step by step.

    I'm thinking to be perfect I'll need adjustable gears.

    1994 Eagle Talon TSi AWD
    2008 Dodge Caliber SRT-4
    1994 Eagle Talon ES
    2006 Suzuki DRZ400SM
    2001 Kawasaki Ninja ZX-9R

  3. #3
    Owner AutoMods's Avatar
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    your probably fine. are you looking at it from the right angle? motor is a bit slanted compared to the chassis lines.

    got a legit timing belt on there? belt tight (tensioner pin pulled)? cam wouldn't have anything to do with it i don't think, even if the cam was made wrong/lobs off, the cam dowel pin still goes into the stock cam gear to allow you to match up the alignment marks

  4. #4
    IAF Team Member Clinical's Avatar
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    if I wasn't so lazy I'd go rotate mine to TDC to take a picture of mine but I guarantee he's seeing the EXACT thing I see with mine. It's definitely not a tooth off but it looks VERY much like it's a half tooth off on my cam gears with everything lined up perfect down low. I'm running gates belt and all new hardware. Pin is pulled, tension set appropriately. Did my belt with the jay racing timing belt tool kit. I can get them lined up perfect when I had the belt off, and I'd get the belt on and EVERYTHING would be lined up perfect. I'd then remove my cam gear tool after setting tension, and then I'd do the 6 rotations. It'd all stay lined up but every time it'd be that little half tooth off.
    I gave up messing with it after some people on the DSMTuners facebook page told me not to worry about it. My car seems perfectly fine so I don't know what to think of it either. I re-did the timing process over and over trying to change it. Soon as I'd start doing the rotations it'd end up the same way. No steps skipped or anything.

    1994 Eagle Talon TSi AWD
    2008 Dodge Caliber SRT-4
    1994 Eagle Talon ES
    2006 Suzuki DRZ400SM
    2001 Kawasaki Ninja ZX-9R

  5. #5
    Moderator DustinsDuster's Avatar
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    the common response i'm getting is to just go off the center marks. apparently the cam gears are interchangeable, and will not all line up straight across. if you look at the gears, you can see the left notch is in the peak of the tooth, and the right is in the valley of the groove, so this makes sense. IIRC, Trevor and i lined up the outer marks, so i'm still thinking both gears mightve been a half tooth off. stay tuned and we'll see how it runs after this.
    Tango 'til they're sore

  6. #6
    Senior Member skipdownstairs's Avatar
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    its off yet I have been standing in your shoes before might have to move the crank one tooth and adjust the top to get it I also have a solid lifter and the rest of the stuff for degreeing in a cam for one of these I was supposed to go down to Brent's and do his but couldn't get the time off to do it your more than welcome to use it


    if you degree them in you will know for sure
    Andy Fangman
    F1X Procharged LS1 Foxbody Mustang
    4.86 147mph
    http://www.youtube.com/user/skipdownstairs

  7. #7
    Admin Drifte's Avatar
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    I remember having this problem with DSM's in particular. My last build went together smoothly so its been a good 8 years since I would have dealt with the issue. Not that it matters, but you dont have balance shafts do you?

  8. #8
    Moderator DustinsDuster's Avatar
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    Balance shafts are removed. I'll let you know Andy- I'm gonna try it with the inner notches lined up and see what happens.
    Tango 'til they're sore

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