CC | Norton Model | Denso Plug |
| 850cc | Commando Interstate and Roadster | W22EP-U |
| 750cc | Commando Fastback, Commando S, Commando Roadster | W22EP-U |
| 745cc | Atlas/Ranger P11A | W24EP-U |
| 650cc | Dominator, Mercury ,Manxman | W22ES-U |
| 600cc | 19R, 19S, 77, 99 OHV | W20ES-U |
| 596cc | Big 4 SV | W20ES-U |
| 500cc | All Models 19.0 mm (3/4”) Heads | W22ES-U |
| 500cc | ES2 OHV 12.7mm (1/2”) Heads | W22FS-U |
| 500cc | 19.00 mm (3/4”) Heads | W22ES-U |
| 500cc | 88SS (OHV) | W22ES-U |
| 500cc | 16H SV | W20ES-U |
| 499cc | 30 (OHV) | W24ES-U |
| 490cc | 500T (OHV) | W20ES-U |
| 384cc | ES400 | W22ES-U |
| 350cc | 40 (OHV) | W24ES-U |
| 350cc | 50 (OHV) Twin Navigator | W22ES-U |
| | Source: 2013 Denso Corporation | |
