From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Table detailing cylinder bore diameter and wear measurements after 15,000 miles.
| Identifier | ExFiles\Box 5a\3\ 03-page072 | |
| Date | 17th December 1931 | |
| CX{Major Len W. Cox - Advertising Manager} - 19 GTV BORES OF CYLINDERS AFTER 15000 MILES | BORE N° | MEASURED AT | DIAMETER | WEAR | |---------|-------------|----------|--------| | 1 | CROWN | 3.1515 | .0015 | | | CENTRE | 3.1515 | .0015 | | | MOUTH | 3.151 | .001 | | 2 | CROWN | 3.1513 | .0013 | | | CENTRE | 3.1514 | .0014 | | | MOUTH | 3.1507 | .0007 | | 3 | CROWN | 3.1517 | .0017 | | | CENTRE | 3.1516 | .0016 | | | MOUTH | 3.1507 | .0007 | | 4 | CROWN | 3.1515 | .0015 | | | CENTRE | 3.1514 | .0014 | | | MOUTH | 3.1505 | .0005 | | 5 | CROWN | 3.1514 | .0014 | | | CENTRE | 3.1514 | .0014 | | | MOUTH | 3.1506 | .0006 | | 6 | CROWN | 3.1513 | .0013 | | | CENTRE | 3.1515 | .0015 | | | MOUTH | 3.1506 | .0006 | DRAWING SIZE 3.150 + 1 DIA | ||