The Stovebolt Site Forums The Shop Area Engine Shop 250/292 fiber/aluminum timing gear questions

I recently bought a low mile 250 to go in my C-10 to replace the very tired 230. I'm a little worried about the timing gear now, though. The 230 I'm sure has an aluminum cam gear and howls loudly above 1,200 or so; I ran the 250 today and couldn't hear the timing gear at all. I didn't have any exhaust hooked up, but if it was anywhere near as loud as the 230 I should have very easily heard it. It should be a '71 truck block, is there any easy way to tell if it has fiber gear?

How loud are the aluminum timing gears normally? I have never heard another six that howls like my 230 in all the youtube clips of them I've seen, so I figure the gears are horribly mismatched or something in that one. What's the normal sound level like? Can you tell the fiber and aluminum cam gears apart by ear?

I'm also probably going to look at a 292 for my C-30 soon to replace the sludged up 195/283 and would like to know if it has the fiber gear or not before I put it in the truck, ideally before I buy it. I think the fiber gears seem to be problematic in truck use, say over 3,000? I will probably cruise at 2,500 most of the time, but (rarely) could potentially run 3,000-3,300 on the highway or if I have to hit third loaded on a hill, and don't want to shear all the teeth off a fiber gear and crash the valvetrain.