| X1/9 Model | Model Year | Chassis Type | Beginning Serial No. | Engine Type |
| Spider | 1974 | 128AS | 0002564 | 128AS.040.4 |
| Spider | 1975 | 128AS | 0025560 | 128A1.040.5 |
| " | " | " | " | 128A1.031.5 |
| Spider | 1976 | 128AS | 0040659 | 128A1.040.5 |
| " | " | " | " | 128A1.031.5 |
| Spider | 1977 | 128AS | 0057030 | 128A1.040.5 |
| " | " | " | " | 128A1.031.5 |
| Spider | 1978 | 128AS | 0074001 | 128A1.040.5 |
| " | " | " | " | 128A1.031.5 |
| Spider | 1979 | 128AS1 | 0093100 | 138AS.040 |
| " | " | " | " | 138AS.031 |
| Spider | 1980 | 128AS0 | 0121001 | 138BS.040 |
| " | " | " | " | 138BS.031 |