1951–1952 288
1951–1952135 hp @ 3600 rpm / 230 lb-ft @ 2000 rpm
Core postwar Packard standard straight-eight
TorqueList Original Technical Art
Packard 288 Thunderbolt Straight-Eight
Inline8 · N/A
Packard · Postwar Thunderbolt Straight-Eight
Packard 288 Thunderbolt Straight-Eight
The short-stroke postwar Packard eight that replaced the older 282 and anchored the company's volume models.
288
Cubic inches
Packard shortened stroke dramatically compared with the earlier 282/356 engines, creating a more modern postwar straight-eight architecture shared conceptually with the 327 and 359.
Key variants
All variants1951–1952 2881954 Clipper 288
Displacement
288 ci
Bore
3.5"
Stroke
3.75"
Years
1948–1954
Key Takeaway
The 288 was part of Packard’s postwar straight-eight redesign, using a 3.50-inch bore and shorter 3.75-inch stroke than earlier engines. That geometry reduced piston speed and created a more modern, compact-feeling powerplant while retaining the familiar L-head layout.
Technical Specifications
- Compression
- 7.0:1 in documented 1951–1952 specification; later 1953–1954 versions increased compression/output by application
- Horsepower
- Output varied by year; about 150 hp in later Clipper specification
- Torque
- 230 lb-ft @ 2000 rpm in documented 1951–1952 specification
- Architecture
- L-head inline eight
- Block
- Cast iron
- Cylinder heads
- Cast iron
- Valvetrain
- Side-valve L-head; hydraulic lifters on selected applications
- Aspiration
- Naturally aspirated
- Fuel delivery
- Carbureted
- Firing order
- 1-6-2-5-8-3-7-4
The 288 was part of Packard’s postwar straight-eight redesign, using a 3.50-inch bore and shorter 3.75-inch stroke than earlier engines. That geometry reduced piston speed and created a more modern, compact-feeling powerplant while retaining the familiar L-head layout.
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
- 288 Thunderbolt motor numbers are series/application-specific; identify by stamped Packard motor number plus 3.50 x 3.75-inch bore/stroke
- Casting numbers
- No single universal 288 casting is retained across 1948–1954 production; verify casting/date with motor number, five-main-bearing block configuration and application.
- Power rating
- Period brake horsepower / SAE gross-era rating
- Horsepower RPM
- 135 hp @ 3600 rpm in documented 1951–1952 specification; later versions reached approximately 150 hp depending year/application
- Torque RPM
- 230 lb-ft @ 2000 rpm in documented 1951–1952 specification
Operating Specs
- Production notes
- Introduced for Packard’s postwar 22nd Series, the 288 used a 3.50-inch bore and 3.75-inch stroke. It shared broad family architecture with the longer-stroke 327 while serving as the standard-displacement engine.
Compatibility Notes
- 288 and many 327 engines share family architecture and bore, but stroke, crank/rod/piston combination, main-bearing count on some 327 applications, compression and carburetion differ.
- Identify motor number and year before mixing cylinder heads; Packard flathead head swaps can change compression ratio materially.
Notable Applications
Packard EightPackard 200Packard Clipper
Strengths
- Shorter stroke than older Packard eights
- Smooth operation
- Strong postwar parts interchange knowledge
Weaknesses / Watch-outs
- Flathead breathing limits power
- Long overall engine length
- Less torque than 327/359 versions
Common Upgrades
- Two-barrel carburetor tuning
- Electronic ignition
- Overdrive transmission
Racing History & Legacy
The 288 Thunderbolt was built for smooth road performance and Packard’s volume models rather than racing. Its importance is as the short-stroke member of the postwar 288/327 engine family.
The 288 became Packard's postwar volume straight-eight and foundation of the final straight-eight generation.
References & Image Credit
Packard bore/stroke comparison
technical reference
Packard Club carburetor reference data
club reference
Packard straight-eight firing-order reference
technical reference
Packard 1950s general engine specifications
historical specification
Packard Club — carburetor and application reference
club reference
Packard Club — year/model/motor-number identification reference
club identification reference
Key Factory / Build Variants
1954 Clipper 288
1954Approximately 150 hp class
Final and higher-output 288 production specification
Engineering Notes Worth Knowing
01
3.50 x 3.75-inch bore and stroke; 288 cu in / 4.7 L.
02
Postwar L-head straight-eight with cast-iron block and head.
03
Later versions produced around 150 hp, with representative torque of 230 lb-ft at 2,000 rpm.
04
Used in Packard Eight, Packard 200, and Clipper.
History · context · related reading
The Story Behind Packard 288 Thunderbolt Straight-Eight
After the war, Packard reworked its straight-eight strategy around the 288/327 family. The 288 was the shorter-stroke volume engine and became the foundation of Packard’s final generation of inline-eights.
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