| Year | 1931 |
| Date | 30-Apr |
| Volume | 64 |
| Issue | 1,564 |
| Page | 421 |
| Category | Petrol Engine Topics |
| Part | |
| Title | A Chat on Mechanical Efficiency |
| Author | Edgar T.Westbury |
| Notes | Improvement, cylinder/piston friction, friction in other mechanical parts, main bearings, big-end bearings, gear friction, pumping losses, auxiliary drives, magneto and coil contact-breakers, circulating pump, cooling fans, lubrication |