| Model | Date of manufacture | Power, kWt | Power HP | Volume cc | Type of construction |
|---|---|---|---|---|---|
| WESTFIELD XTR 2 | 09.2001 - 03.2004 | 132 | 180 | 1299 | Convertible |
| WESTFIELD XTR 4 | 03.2004 - 12.2008 | 143 | 194 | 1781 | Convertible |
| WESTFIELD XTR 4 | 03.2004 - 06.2006 | 165 | 224 | 1781 | Convertible |