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Chrysler RB 440 TNT specs: 440 ci (7.2L) 8-cylinder, 4.319 x 3.752 in (109.7 x 95.3 mm) bore and stroke. Rated 365-375 hp, 1966–1971.
The Chrysler RB 440 TNT is oversquare — the 4.3189" bore exceeds the 3.752" stroke by 15.1% — a layout that favors airflow and RPM over leverage at the crank. The 3.752" stroke puts mean piston speed at 4,000 ft/min around 6,400 RPM, which is where a production bottom end is generally considered at its limit. A rod ratio of 1.804 is long by production standards — less side-load on the cylinder wall and gentler piston acceleration around TDC, the geometry that tolerates high RPM. Each of the 8 cylinders displaces 55.0 ci (901 cc).
It is one of 4 engines in the Chrysler 440ci family, all of them 440 ci — the differences between them are in compression, heads and rating, not displacement. 6 factory variants share these dimensions, rated from 365 to 375 hp across 1966–1971.
| Displacement | 440 ci / 7.2 L |
|---|---|
| Bore | 4.3189" |
| Stroke | 3.752" |
| Cylinders | 8 |
| Configuration | V8 |
| Compression ratio | 9.5–10.1:1 (published figures vary) |
| Rod length | 6.768" |
| Rod ratio | 1.804 |
| Bore/stroke ratio | 1.151 |
| Block material | cast iron |
|---|---|
| Head material | cast iron |
| Valvetrain | OHV |
| Fuel type | gas |
| Firing order | 1-8-4-3-6-5-7-2 |
| Advertised HP | 365–375 hp |
| Years | 1966–1971 |
| Year | Version | HP @ rpm | Torque @ rpm | Comp. | Duration int / exh | Valve lift int / exh | LSA |
|---|---|---|---|---|---|---|---|
| 1967 | gross | 375 @ 4600 | 480 lb-ft @ 3200 | 10.1:1 | — | — | — |
| 1968 | gross | 375 @ 4600 | 480 lb-ft @ 3200 | 10.1:1 | 268° / 284° | 0.450" / 0.458" | 115° |
| 1969 | gross | 375 @ 4600 | 480 lb-ft @ 3200 | 10.1:1 | 268° / 284° | 0.450" / 0.465" | 115° |
| 1970 | gross | 375 @ 4600 | — | — | 268° / 284° | 0.450" / 0.458" | 115° |
| 1971 | gross | 370 @ 4600 | 480 lb-ft @ 3200 | 9.5:1 | — | — | — |
Factory specification sheet. Durations are the factory's advertised figures at the basis printed on the sheet, not duration at .050" lift; lobe separation is calculated from the printed valve timing.
| Bore/stroke character | 1.151 — oversquare — bore exceeds stroke, which favours higher RPM and larger valves |
|---|---|
| Mean piston speed at 6,000 RPM | 3,752 ft/min — in the range typical of performance street engines |
| Rod ratio | 1.804 — long — less side loading on the cylinder wall, favours high RPM |
| Displacement per cylinder | 55.0 ci |
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 |
|---|---|---|
| 1966 | 365 hp | RB 440 TNT |
| 1967 | 375 hp | RB 440 TNT |
| 1968 | 375 hp | RB 440 TNT |
| 1969 | 375 hp | RB 440 TNT |
| 1970 | 375 hp | RB 440 TNT |
| 1971 | 370 hp | RB 440 TNT |
2 factory vehicles, 1966–1971. Each year opens that model's engine table.