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Presumably this 450 has the M117 engine...a cast iron block?.
The metallurgy of the MB iron blocks has a very high silica content.
This makes the bores last a long time.
Oldsmobile used a similar iron in the 455's.
When ringing these engines you must ....
.......Never use DEVES rings..
..Never use synthetic assembly oil..
..Never use oil additives.
...Never use synthetic before 8000 miles..
..Never use low tension ring sets....
..Always break in with non detergent oil for first 1000 miles...
If he's a machinist ask him if he honed the cylinders with a #280 grit stone,
after that touch with #400 grit stone or an abrasive nylon brush
honing tool to plateau the surface...
Brush the cylinders after honing with a good quality soft brush tool to
clean away the torn and folded metal debris.
Finally...clean clean clean....the cylinder bores.
This has worked for me and no oil burning afterward.
The alloy blocks used later where not good candidates for boring as
they needed special preparation too for good sealing. These later
116 and 117 blocks needed careful finishing to allow the silica grains
to be proud of the bore surface on which the rings rode.
Now there are bore preparations and piston coatings to help life and sealing.
BMW uses a nikosil deposit on the bores and one company is lazer cutting
40 micron slots in the upper part of the cylinder to retain oil
and increase life of the new very thin ring sets.
Personally I just re ring the alloy blocks if the bore wear is minimal using a
1st oversize ring set hand fitted to each std bore.
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