Engine Identification: Notes
First two letters in production code number identify engine displacement, carburetion, and compression ratio. Production code number is located on right side of block below and between two center spark plugs (2.25", 300", 340"); first and second spark plugs from front (400", 430").
| Engine | Compression Ratio | Code Letters | ||
|---|---|---|---|---|
| 225" 2-Bbl. V6 | 9.0-1 | NH | ||
| 300" 2-Bbl. V8 | 9.0-1 | NL | ||
| Export | 7.6-1 | NM | ||
| 340" 2-Bbl. V8 | 9.0-1 | NA | ||
| Export | 8.1-1 | NX | ||
| 4-Bbl. V8 | 10.25-1 | NB | ||
| 400" 4-Bbl. V8 | 10.25-1 | NR | ||
| 430" 4-Bbl. V8 | 10.25-1 | MD, ND | ||
| Export | 8.75-1 | NF | ||