3.910 + a few lines
You need to ream the ridge, get rid of it, that will/can cause issues with a new square ring smacking into a coved wall/ridge.
Lotta failures caused by that, and carboned up ring grooves.
I would re-ring that in a heartbeat, as I have many others.
Ring grooves need to be cleaned out, lands checked, stone hone to "fair"/straighten the cyl walls.
I make a "shoe" outta pieces of "scotch-bright" pads to fit over the stones for final finish, especially with moly rings.
You can see by the ridge reamer, it's done dozen and dozens of engines since I bought it new in the 70's.
It wouldn't have been used often, if re-rung engines didn't work out, customers wouldn't permit it, nor would my pride .
I serviced many of these vehicles for years/decade, and would have been aware of any failures, there were a very few, that we expected.
Fact .
You need to ream the ridge, get rid of it, that will/can cause issues with a new square ring smacking into a coved wall/ridge.
Lotta failures caused by that, and carboned up ring grooves.
I would re-ring that in a heartbeat, as I have many others.
Ring grooves need to be cleaned out, lands checked, stone hone to "fair"/straighten the cyl walls.
I make a "shoe" outta pieces of "scotch-bright" pads to fit over the stones for final finish, especially with moly rings.
You can see by the ridge reamer, it's done dozen and dozens of engines since I bought it new in the 70's.
It wouldn't have been used often, if re-rung engines didn't work out, customers wouldn't permit it, nor would my pride .
I serviced many of these vehicles for years/decade, and would have been aware of any failures, there were a very few, that we expected.
Fact .