Does anyone know how many miles we should replace the timing set ? I have a 302 with about 95k miles on her . And would the chain be fine to change out or both gears . 1 more question is gear drive on a older engine , has anyone done gear drive and any clearance problems or any problems at all ? Love the wine of a gear drive . Thanks and if you installed gear drive pics would be nice .

 

If you have to have a number, 100K is what I would give. I have had chains(double roller) last the initial life of the engine (130-200K) without breaking, and not have very much slack in them. If you have a double roller timing set, just replace the chain UNLESS there is signifcant wear on the teeth. If you have the old school type, replace the entire thing. A good indicator of a worn chain is to put a wrench on the crank, and back it off while watching the rotor. If there is a slight lag between turning the crank, and when the rotor moves, its time for a chain. 5* worth of crank movement with no rotor movement is acceptable, anything less I would say its time to go. Another way to check is to take out your fuel pump, you should be able to check for slack thru that passage way.

I have not done any gear drive installs, but I have read a few installation procedures, most indicate that clearancing/machining is required. I personally do not like gear drives on my rigs. They sound awesome, especially on radical engines, but it makes it a challenge to "listen" to your motor when you are trying to diagnose strange noises.