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Old 01-20-2020, 11:45 PM
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hgerhardt hgerhardt is offline
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Join Date: Dec 2003
Location: CA
Posts: 657
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Quote:
Originally Posted by 67drake View Post
Yup. My 96’s cc’ed around the 100-102 range. I had a few sunk valves too
Yeah, I had a set of 96's years ago on a 455. Engine ran great until a lifter bottomed out. One of the exhaust valves had sunk about .150 and several others were over .100 deep. This was after about 50k miles.

GM claimed that all '71 and up heads had hardened exhaust seats. Obviously my heads did not come that way.

So, if you intend to do any serious amount of street miles, hardened exhaust seats would be a good idea.