Only 2 things cause bent timing rings:
1) Over tightening the screws down. Lightly screw in each screw, when each has started to snug, tight another 1/4 to 1/2 turn. Thats all u should need.
2) Often overlooked but if you where around before rebuildable stock motors you would remember that we used to pop endbells off especially in pan car classes. Not as much an issue with touring car but still it happens. With rebuildables the timing ring prevents endbells from poping off, but the result is during a hard hit something has to give and to extent i think the timing rings bend. They are a soft steel and are probably hot during most runs. So stay off the walls will help reduce bent rings as well. The hits im talking about are side swiping walls and stuff. Anything where your car has hit something sideways.
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