If a different TYPE of camshaft, i.e. a flat tappet is swapped into a roller rocker block, is it even remotely possible that the cam gear is smaller than the stock gear? Which would slowly but surely lead to a change in timing settings, over slow intervals of time? I'm chasing a hunch...any info would be appreciated.

 

Yes, it's a different timing set altogether IIRC.
I don't think that would slowly change your ignition timing settings though. A loose distributor bolt would do that.

 

Factory roller cams use a different timing set than the flat-tappet and retro-roller cams, but the sizes should be about the same.

Regardless, there's no way it could cause timing to slowly "drift".

 

Thanks. I keep checking the dist. bolt. and it's tighter than ever. But my timing slowly goes to 18 advanced, and then it fouls my plugs. any thoughts?

 

It's unusual that it advances. Usually if there was a mechanical problem it would retard the timing.

 

how slowly is slowly? days? minutes? months?

Balancer ring slipping, but again, I think that would show up as retard.

It advances to 18*? Not 19, not 20, not 16, but 18? Don't you think that's kind of strange?