I was wondering if there was a way of figuring out for sure what type of timing gears came in my car. GM loved to use those wonderfully awful nylon coated timing gears. I think I will have to take off the cover, but as it is the 3.8 from the late seventies, it has that complex looking timing cover, i am a bit worried about it. It almost looks like the water pump is integrated into the thing.

As it is an interference engine, I need to figure this out before the thing goes.

 

I'd assume they were nylon coated and just go ahead and replace them. Usually they don't fail catastrophically but allow the timing chain to skip a tooth or two which changes the timing which will make the engine hard to start, if at all.