1935 One Twenty 257
1935110 hp @ 3850 rpm; 203 lb-ft @ 2000 rpm
First engine of Packard’s volume-market One Twenty line
TorqueList Original Technical Art
Packard 257 One Twenty Straight-Eight
Inline8 · N/A
Packard · One Twenty Straight-Eight
Packard 257 One Twenty Straight-Eight
The compact 1935 Packard Eight that brought modern independent front suspension and a lighter engine package to the new One Twenty.
257
Cubic inches
The 257 helped launch Packard's lower-priced One Twenty line and showed the company could build a smaller, lighter straight-eight without abandoning Packard smoothness.
Key variants
All variants1935 One Twenty 257
Displacement
257 ci
Bore
3.25"
Stroke
3.875"
Years
1935
Key Takeaway
The 257 was a relatively compact Packard L-head straight-eight created for the new One Twenty line. Its 3.25-inch bore and 3.875-inch stroke, 6.5:1 compression, and five-main-bearing support balanced traditional Packard smoothness with a lighter, more affordable package.
Technical Specifications
- Compression
- 6.5:1
- Horsepower
- 110 hp
- Torque
- 203 lb-ft @ 2000 rpm
- Architecture
- L-head inline eight
- Block
- Cast iron
- Cylinder heads
- Cast iron
- Valvetrain
- Side-valve L-head
- Aspiration
- Naturally aspirated
- Fuel delivery
- Carbureted
- Firing order
- 1-6-2-5-8-3-7-4
- Main bearings
- 5
The 257 was a relatively compact Packard L-head straight-eight created for the new One Twenty line. Its 3.25-inch bore and 3.875-inch stroke, 6.5:1 compression, and five-main-bearing support balanced traditional Packard smoothness with a lighter, more affordable package.
Internal Specifications
Variant-specific values are labeled. Engine families that span multiple years or RPOs can have different heads, cams, induction and rotating parts, so the exact code/year always takes priority.
Identification & Output
- Engine codes / RPO
- 1935 One Twenty motor-number/vehicle-series identification; no modern RPO-style engine code
- Casting numbers
- No single universal 257 block/head casting is retained here; identify by Packard motor number, 3.25 x 3.875-inch bore/stroke, model year and One Twenty application.
- Power rating
- Period brake horsepower / SAE gross-era rating
- Horsepower RPM
- 110 hp @ 3850 rpm
- Torque RPM
- 203 lb-ft @ 2000 rpm
Operating Specs
- Production notes
- Introduced with the One Twenty for 1935, the 257 used a 3.25-inch bore and 3.875-inch stroke, 6.5:1 compression and a single carburetor. It was enlarged to 282 cid for 1936.
Compatibility Notes
- The 257 is the one-year first-generation One Twenty straight-eight; do not assume later 282 internals are identical despite the shared 3.25-inch bore.
- Use Packard motor number, bore/stroke and year-specific external hardware to identify a loose engine before ordering pistons, gaskets, ignition or clutch parts.
Notable Applications
1935 Packard One Twenty
Strengths
- Compact by Packard standards
- Five-main-bearing crank support
- Strong period torque
Weaknesses / Watch-outs
- One-year displacement
- Flathead breathing limits performance
- Original components are restoration-focused
Common Upgrades
- Period-correct carburetor rebuild
- Electronic ignition hidden in stock distributor
- Cooling-system restoration
Racing History & Legacy
The 257 was developed for the new One Twenty’s combination of refinement, lighter weight and everyday performance rather than a factory racing program. Its importance is commercial and engineering: it powered the car that broadened Packard’s market during the Depression.
The 257 was the short-lived first step toward the better-known 282 One Twenty engine.
References & Image Credit
Packard Club 1935 One Twenty reference data
club reference
Packard bore/stroke reference
technical reference
Packard straight-eight firing-order reference
technical reference
1935 Packard One Twenty specifications
historical specification
Packard Club — year/model/motor-number identification reference
club identification reference
Key Factory / Build Variants
Engineering Notes Worth Knowing
01
3.25 x 3.875-inch bore and stroke; 257 cu in / 4.2 L.
02
L-head straight-eight with cast-iron block and head.
03
Factory output: 110 hp with about 203 lb-ft at 2,000 rpm.
04
Used for the 1935 Packard One Twenty.
History · context · related reading
The Story Behind Packard 257 One Twenty Straight-Eight
The One Twenty changed Packard’s business by bringing the brand into a lower price class without abandoning the smooth straight-eight character buyers expected. Its one-year 257 engine was the first step in that strategy.
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