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I obtained a dial indicator and then experimented with ways to find actual TDC and to measure cam movement with as little disassembly as possible. I'm optimistic that I finally have this cam degreeing thing understood at an apprentice level, or at least it isn't the occult ritual I perceived it to be just a few weeks ago. I'm looking for some confirmation from you guys to make sure I understand properly the information I now have before I plow forward and pull apart the front of the engine to make the adjustment I think I need to make. I've attached pictures so you can see yourself the results of verifying my intake cam lobe position. To explain, here's what's in the pictures:
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Dial indicator reading the intake cam opening at .020. From all my research (my Haynes manual, info I've read on this forum, etc), the stock rocker arm ratio is 1.5 and the ONLY place I could get a reliable reading without taking apart the rocker assembly is on the retainer. So, the indicated .030 opening reflects .020 x 1.5.
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My actual TDC was found to be dead-on and the "pointer" is the yellow mark on my factory probe tube. With that being said, I turned the engine clockwise until I achieve the valve opening of .030 and my effective crank measurement is 16 degrees BTDC. I perceive this is my issue, since the cam card indicates it should be 24 degrees BTDC. This suggests to me, if I'm not mistaken, that I'm likely off a tooth on my cam gear.
Does anyone see any problems with my methods or diagnosis? If not, I'll tear into it and see if this fixes my rough running!