I'm rebuilding my turbo-charged 1980zx engine. I took the head off and looked at the o-rings on the block to find that a couple of them have little grooves and dings in them. The turbo is putting out around 16 pounds of boost and has been on the car for years. I purchased the car from my brother and he ran it hard for a year and a half. The head gasket blew once when someone was test driving it and red-lined it. I have no intention of reving that high and was wondering if the o-rings will still work as they are supposed to. If I put a head gasket on,torque it down and then take it off again and find that a ring has been made for each gasket ring does that mean the o-rings are adequate? Any help will be greatly appreciated. Thanks.