When did GM stop using the nylon coated gears on their SBC Timing Chain

[texas-topper]

Hi All,

Quick question,....If, and when did GM stop using the nylon toothed sprockets on their timing chain setup on small block chevy engines?

Back in 1979 I had a 1972 Chevy truck with a sbc 350. I found out the hard way it had the nylon teeth on a steel sprocket setup for the timing chain. Needless to say I learned how to replace the timing chain way back then.


I now have a fairly low milage (54,000) 1978 Chevy Big 10 with a 350 and I am concerned it could have the same nylon gears as the '72 chevy had. Let me know when and if GM ever stopped using tthe nylon tooted gears.

Thanks for the help,

Ken