See other engines in this family
Chevrolet 348ci specs: 348 ci (5.7L) 8-cylinder, 4.125 x 3.25 in (104.8 x 82.6 mm) bore and stroke, 11.25:1 compression. Rated 320-350 hp, 1959–1961.
The Chevrolet 348ci is oversquare — the 4.125" bore exceeds the 3.25" stroke by 26.9% — a layout that favors airflow and RPM over leverage at the crank. The 3.25" stroke does not reach 4,000 ft/min of mean piston speed until about 7,400 RPM, so piston speed is not what limits this engine's revs — valvetrain and breathing are. Each of the 8 cylinders displaces 43.5 ci (713 cc).
11.25:1 on iron heads is high enough that pump premium or better is normally required, and iron holds heat, so it is the less forgiving side of that line.
It is one of 13 engines in the Chevrolet 348ci family, all of them 348 ci — the differences between them are in compression, heads and rating, not displacement. 6 factory variants share these dimensions, rated from 320 to 350 hp across 1959–1961.
| Displacement | 348 ci / 5.7 L |
|---|---|
| Bore | 4.125" |
| Stroke | 3.25" |
| Cylinders | 8 |
| Configuration | V8 |
| Compression ratio | 11.25:1 |
| Bore/stroke ratio | 1.269 |
| Block material | cast iron |
|---|---|
| Head material | cast iron |
| Valvetrain | OHV |
| Valves per cylinder | 2 |
| Induction | 4-bbl Carter AFB |
| Advertised HP | 320–350 hp |
| Years | 1959–1961 |
| Bore/stroke character | 1.269 — oversquare — bore exceeds stroke, which favours higher RPM and larger valves |
|---|---|
| Mean piston speed at 6,000 RPM | 3,250 ft/min — conservative for a street engine |
| Displacement per cylinder | 43.5 ci |
| Static compression | 11.25:1 — high enough that pump premium or better is normally required |
Each link opens the calculator with this engine's specs already filled in.
These records share identical bore, stroke, displacement and compression. They differ by model year and factory power rating.
| Year | Advertised HP | Code |
|---|---|---|
| 1959 | 320 hp | Turbo-Thrust Special, RPO 577 |
| 1959 | 335 hp | Super Turbo-Thrust Special, RPO 574 |
| 1960 | 320 hp | Turbo-Thrust Special, RPO 577 / 590 |
| 1960 | 335 hp | Super Turbo-Thrust Special, RPO 574 / 571 |
| 1961 | 340 hp | Turbo-Thrust Special, RPO 572 |
| 1961 | 350 hp | Super Turbo-Thrust Special |