1953 322 Roadmaster
1953188 hp class
Launch-year Buick Nailhead V8
Buick 322 Nailhead V8 enginePhoto: Mr.choppers — CC BY-SA 3.0 — via Wikimedia Commons · CC BY-SA 3.0
Buick · Nailhead V8
Buick 322 Nailhead V8
Buick's first production Nailhead displacement and the engine behind the early-1950s performance push.
322
Cubic inches
The 322 introduced Buick's new short-stroke, high-torque OHV V8 architecture for 1953 and formed the basis of the Nailhead family that would grow to 425 cubic inches.
Key variants
All variants1953 322 Roadmaster1955 high-output 3221956 322
Displacement
322 ci
Bore
4"
Stroke
3.203"
Years
1953–1956
Key Takeaway
The 322 launched Buick's Nailhead family with a large 4.00-inch bore, short 3.203-inch stroke, and nearly vertical valve layout. The unusual head design kept the engine externally narrow and delivered the low-speed torque Buick prized.
Technical Specifications
- Compression
- 1955: 8.4:1 manual / 9.0:1 Dynaflow; earlier and 1956 versions varied
- Horsepower
- Varies by year/application; see documented variants
- Torque
- 330 lb-ft @ 3000 rpm in documented 1955 high-output specification
- Architecture
- 90-degree OHV V8
- Block
- Cast iron
- Cylinder heads
- Cast iron
- Valvetrain
- Pushrod OHV, Nailhead valve layout
- Aspiration
- Naturally aspirated
- Fuel delivery
- Carbureted
- Firing order
- 1-2-7-8-4-5-6-3
- Main bearings
- 5
The 322 launched Buick's Nailhead family with a large 4.00-inch bore, short 3.203-inch stroke, and nearly vertical valve layout. The unusual head design kept the engine externally narrow and delivered the low-speed torque Buick prized.
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
- 1953–1956 322s are identified primarily by stamped engine serial/vehicle series; Buick did not yet use the later universal two-letter production-code system
- Casting numbers
- 1165165 (1953–1956 322 block reference), 1169334 (1956–1959 322-family block reference), 1165549 / 1166349 / 1168930 / 1169349 (322 head references)
- Power rating
- SAE gross / period brake horsepower
- Horsepower RPM
- 236 hp @ 4600 rpm in documented 1955 Century/Super/Roadmaster specification
- Torque RPM
- 330 lb-ft @ 3000 rpm in documented 1955 specification
Rotating Assembly
- Rod length
- 6.000 in
Operating Specs
- Production notes
- Introduced for 1953 as Buick’s first modern OHV V8, the 322 used a 4.00-inch bore and short 3.203-inch stroke. Output climbed rapidly during its four-year run before Buick enlarged the family to 364 cid for 1957.
Compatibility Notes
- Early 264/322 Nailheads share more architecture with each other than with the later 364/401/425 group; verify intake, exhaust, mounts and transmission interface before interchange.
- Engine serial and casting/date should be used together because a bare casting alone does not document the original vehicle or factory power specification.
Notable Applications
Buick RoadmasterBuick SuperBuick Century
Strengths
- Large 4.00-inch bore for an early-1950s V8
- Compact external dimensions
- Distinctive low-rpm torque delivery
Weaknesses / Watch-outs
- Unusual cylinder-head layout limits modern airflow compared with later designs
- Heavy and specialized compared with mainstream later V8s
Common Upgrades
- Dual-quad or multiple-carb induction
- Electronic ignition conversion
- Improved cooling and sealing
Racing History & Legacy
The 322 helped make mid-1950s Buick Century models famous for combining the lighter Special body with Roadmaster power. It was a strong high-speed road-car engine, although Buick did not mount a factory racing program comparable to later dedicated muscle-era Stage packages.
The 322 launched one of Buick's most recognizable engine families.
References & Image Credit
Engine image: Mr.choppers — CC BY-SA 3.0 — via Wikimedia Commons · CC BY-SA 3.0 · source
Team Buick Nailhead specifications
technical reference
Buicks.net Nailhead casting numbers
technical reference
1955 Buick factory-spec compilation — 264/322 output, torque and firing order
historical factory specification
Team Buick — Nailhead block/head casting numbers
technical reference
Team Buick — 1953–1958 Buick engine identification
identification reference
Key Factory / Build Variants
1955 high-output 322
1955236 hp / 330 lb-ft
Century/Roadmaster performance specification
1956 322
1956Application dependent
Final and highest-development 322 production year
Engineering Notes Worth Knowing
01
322 cu in / 5.3 L with 4.00 x 3.203-inch bore and stroke.
02
90-degree OHV Nailhead V8.
03
Carbureted and naturally aspirated.
04
Documented 1955 high-output torque: about 330 lb-ft.
History · context · related reading
The Story Behind Buick 322 Nailhead V8
The 322 introduced the architecture that would make Buick's early V8s instantly recognizable. Its narrow package and torque-heavy personality became the defining traits of the Nailhead family.
TorqueList Garage Reference Series
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