1917 Cadillac Type 55: 125-Inch Chassis with Electric Starting

Cadillac sold the Type 55 for 1917 with a 314-cubic-inch L-head V8, commonly rated at 70 horsepower in factory specifications. Its 125-inch-wheelbase chassis carried open touring bodies as well as roadsters, coupes, sedans, and formal closed coachwork, all driven through a three-speed manual transmission.

The Type 55 followed Cadillac's Type 51 and Type 53 and belongs to the sequence that continued through the Type 57, Type 59, and Type 61. These cars developed the production V8 formula Cadillac had introduced for 1915, while retaining the separate-frame construction, mechanical brakes, leaf springs, and coachbuilt body practices expected before the widespread adoption of all-steel bodies.

Best known for refining Cadillac's pioneering series-production V8 during the First World War, the Type 55 joined usable low-speed torque, standardized left-hand controls, and electric starting in a chassis suitable for both owner-driven touring and formal bodywork.

Quick Facts

The essential Type 55 specifications are relatively consistent across surviving factory literature, although body dimensions and finished weights differed substantially among open, closed, and formal styles.

The model designation identifies the chassis series rather than one fixed body. Two surviving Type 55s can therefore differ markedly in seating capacity, roof construction, trim, windshield treatment, and overall weight while remaining mechanically authentic examples of the same Cadillac type.

Why the Type 55 Matters

Cadillac's first production V8, the Type 51 of 1915, converted a complicated engine layout into a repeatable manufacturing proposition. By 1917, the Type 55 showed that the V8 was no short-lived prestige experiment. Cadillac had made it the core of a catalog that covered owner-driven roadsters, family touring cars, enclosed sedans, and chauffeur-operated formal cars.

The engine also gave Cadillac an answer to increasingly ambitious multi-cylinder competitors. Packard's Twin Six brought twelve-cylinder smoothness to the same upper reaches of the American market, while Peerless was another prominent V8 manufacturer. Cadillac relied on eight-cylinder torque, electric starting, and standardized controls rather than simply increasing cylinder count.

The Type 55 deserves separate treatment because 1917 was not an anonymous interval between better-known models. The United States entered the First World War that year, material and manufacturing priorities were changing, and large touring cars had genuine military and institutional uses. Surviving 1917 Cadillacs preserve the engineering state of the marque immediately before the Type 57 carried the design into the postwar period.

Historical Context and Development

From the Type 51 to the Type 55

Cadillac had already built its reputation around interchangeability, precision manufacture, and the electric self-starter before it adopted the V8. The 1915 Type 51 placed two banks of four cylinders on a common crankcase, producing a shorter power unit than a comparable straight-eight would have required. The Type 53 followed for 1916, and its arrangement of a left-hand steering wheel, centrally placed gear lever and hand brake, plus clutch, brake, and accelerator pedals closely anticipated the control pattern later adopted throughout the industry.

The Type 55 retained that practical architecture rather than chasing novelty for its own sake. Detail revisions accompanied annual model changes, but Cadillac's basic priorities remained easy starting, smooth torque, durable touring ability, and controls that did not demand the rituals associated with many large Edwardian cars.

Design and Coachwork

A Type 55 has the tall, formal proportions of a late brass-era luxury car without depending on exposed brass for visual effect. The radiator stands nearly vertical, separate front and rear fenders frame large artillery wheels, and the hood is long enough to advertise the compact but substantial V8 beneath it. Open cars generally have upright windscreens and broad passenger compartments, while closed bodies add a tall greenhouse dictated by hat-wearing occupants and the seating conventions of the period.

Cadillac supplied catalog bodies, but the era's construction methods make body identity a serious research subject. Structural wood, sheet-metal skins, upholstery, roof materials, lamps, and hardware may have been repaired or altered repeatedly. A body that looks suitably old is not automatically the body originally installed on a particular chassis.

Competition and Wartime Conditions

The American luxury market was moving quickly toward multi-cylinder engines. Packard promoted the Twin Six, Peerless offered V8 power, and manufacturers including Pierce-Arrow maintained strong reputations with large six-cylinder cars. Cadillac's proposition centered on a comparatively compact V8, a comprehensive electrical system, and production methods intended to make a technically advanced car dependable in routine service.

The Type 55 was not a homologation model and did not emerge from a factory racing program. Its significance came from production engineering and road use. Large American touring cars of this period also served staff, transport, and institutional roles during wartime, but any claim that a particular surviving car saw military service requires period records rather than later-applied paint or insignia.

Engine and Drivetrain

314-Cubic-Inch L-Head V8

The Type 55's water-cooled V8 displaced approximately 314 cubic inches, or 5.15 liters, from a 3.125-inch bore and 5.125-inch stroke. Its long-stroke proportions favored useful torque at modest crankshaft speeds. The side-valve, or L-head, arrangement placed the valves in the block beside the cylinders, avoiding the exposed rocker gear and additional moving parts associated with contemporary overhead-valve designs.

Cadillac's early V8 used separate cylinder banks assembled to a common crankcase. Mixture distribution, cooling balance, bearing condition, and accurate ignition timing are consequently central to a successful rebuild. The engine's 70-horsepower rating should be understood in period context, not compared directly with modern standardized net output.

Induction, Ignition, Lubrication, and Cooling

A carburetor supplied the naturally aspirated engine, with intake passages distributing mixture to both banks. Correct carburetor specification and linkage matter because later replacements can make a car easier to operate while removing one of the most visible pieces of period equipment. The Delco electrical installation incorporated battery-and-coil ignition, electric starting, and lighting, all major conveniences when hand cranking remained familiar to motorists.

An engine-driven lubrication system circulated oil through the power unit, while water circulation, the radiator, and a mechanically driven fan managed heat. Restorers must treat sludge, restricted water passages, corroded jackets, worn pumps, and aged radiator cores as connected problems. A freshly rebuilt engine can still overheat if the rest of the cooling circuit has only been cosmetically restored.

Clutch, Gearbox, and Final Drive

A foot-operated clutch connected the V8 to a three-speed selective manual gearbox. The transmission sent power through a propeller shaft to the rear axle. Period documentation and surviving assemblies should be consulted before specifying internal clutch details because components may differ by production date and many cars have received replacement parts during more than a century of repair.

The following figures describe the core Type 55 powertrain. Torque, compression ratio, and maximum engine speed are omitted because reliable Type 55-specific figures are not consistently published in surviving reference material.

The bore and stroke explain much of the car's road character. This is an engine intended to pull cleanly from low speed and move a heavy coachbuilt body without constant shifting, not one designed to be extended toward a high engine-speed limit.

Chassis, Suspension, and Braking

The Type 55 used a separate frame beneath a body whose structure included substantial timber. Semi-elliptic leaf springs supported rigid axles at both ends. The layout was robust and familiar to period mechanics, but its behavior depended heavily on spring condition, shackle wear, wheel alignment, tire construction, and the rigidity of the body mounted above it.

Mechanical brakes acted at the rear rather than all four wheels. Steering was unassisted, and large-diameter wheels reduced rolling resistance and helped the car cross rutted surfaces. The basic chassis specification is concise, but every listed component can conceal expensive wear.

Rear-only braking is the defining dynamic limitation for modern use. Correct adjustment, equalized linkage, true drums, sound wheel bearings, and suitable tires are not optional details. Added speed from an over-restored engine or changed axle ratio does not increase the chassis's ability to stop.

Driving Experience and Road Manners

A properly sorted Type 55 moves away with deliberate authority rather than abrupt acceleration. The long-stroke V8 delivers its useful work low in the rev range, and the driver can allow the engine to pull instead of repeatedly working the gearbox. Throttle response depends greatly on carburetor condition and ignition timing; hesitation is often a service fault rather than an inherent characteristic.

The gear lever requires measured movements and a sympathetic pause between ratios. There are no modern synchronizers to conceal poor timing, so smooth double-declutching and an understanding of engine speed reward the driver. Clutch take-up should be progressive, although oil contamination, warped parts, or incorrect adjustment can produce judder.

At parking speed the steering is heavy, especially if tire pressures are low or kingpins and steering joints are dry. Once moving, the large wheel provides leverage and the Cadillac settles into the steady directional rhythm expected of a long-wheelbase touring car. Worn shackles or loose steering joints turn that measured response into wander.

Leaf springs and tall tires absorb the broken, unpaved surfaces for which the chassis was designed, but the body rolls and pitches more than a later car. Braking demands anticipation. A Type 55 is most convincing when driven within the cadence of 1917 roads, using engine compression, clear sightlines, and generous stopping distance.

Identification and Originality

Chassis, Engine, and Body Evidence

The Type 55 designation is the starting point, not a complete modern VIN decoder. Collectors should compare the chassis or serial stamping, engine number, body number, data plates, and surviving paperwork with recognized Cadillac club records and period parts books. A newly reproduced plate does not establish the identity of the frame beneath it.

The modern phrase “matching numbers” must be applied carefully. Early Cadillac documentation does not always provide the build-sheet-style chain of evidence expected for a postwar collector car. An engine whose number and physical specification fit the chassis is desirable, but a defensible claim of factory-original installation requires period records or an accepted sequence supported by marque specialists.

Correct Equipment

High-value details include the correct carburetor type, starter and generator equipment, distributor, manifolds, water fittings, control linkages, lamps, instruments, wheel hardware, hubcaps, radiator shell, and steering controls. Components from the Type 57, Type 59, Type 61, or other large period Cadillacs can look convincing while differing in casting, dimensions, attachment, or date.

Body originality is often harder to establish than mechanical identity. Timber frames decay, open bodies are easier to recreate than formal closed bodies, and practical owners historically converted damaged sedans into tourers or speedster-style cars. A handsome recreated body can be enjoyable, but it should not be represented as original coachwork without photographic and documentary support.

Finishes and Documentation

Modern paint-code logic does not translate neatly to a 1917 Cadillac. Factory catalogs, sales literature, early photographs, paint traces in protected areas, upholstery remnants, and body-builder evidence provide a stronger basis than a recently assigned color name. Deep gloss, perfectly flat panels, and extensive bright plating may exceed the materials and surface preparation of the original car.

Useful documentation includes old registrations, title history, engine and body photographs taken before restoration, invoices, correspondence, club judging sheets, and records from long-term owners. These files can distinguish a preserved car, an old sympathetic restoration, and a newly assembled car built around a genuine chassis.

Type 55, Type 57, Type 59, and Type 61 Variants

The four type numbers identify successive Cadillac chassis developments rather than trim levels available simultaneously. Model-year boundaries and catalog descriptions should be checked against individual serial evidence, particularly when an old registration uses the year of first sale instead of the manufacturer's intended model year.

Exact production totals for each body and chassis type are not consistently presented across surviving references. The body itself can also blur distinctions because coachwork was repaired, transferred, or recreated. Mechanical dimensions, number evidence, and period photographs carry more authority than a title description alone.

Performance and Dimensional Specifications

Standardized acceleration tests were not normal practice in 1917, and credible Type 55-specific quarter-mile or 0-to-60 mph results are not generally available. Top speed and weight also changed with body type, passenger load, gearing, tires, and road conditions, so unsupported single figures would give a false impression of precision.

The absence of trustworthy acceleration data is itself instructive. Buyers evaluated a large Cadillac by its ability to start reliably, climb in a high gear, carry a full body and passenger load, and maintain progress over poor roads. Those qualities mattered more than a standing-start figure.

Compared With Related Cadillacs

Type 53 versus Type 55

The 1916 Type 53 is especially relevant because its control layout helped establish the left-hand steering and three-pedal arrangement familiar today. The Type 55 continued the same 314-cubic-inch V8 concept into 1917. For collectors, the distinction rests in year-specific chassis, fittings, number sequences, and coachwork evidence rather than an obvious change in cylinder count or basic drivetrain form.

Type 57 versus Type 55

The Type 57 succeeded the Type 55 for 1918 and continued through 1919. Its close mechanical relationship makes it a frequent source of replacement components, but interchangeability should never be assumed from appearance. Castings, accessories, brackets, controls, and body hardware must be checked against the correct parts literature.

Type 59 and Type 61 versus Type 55

The Type 59 and Type 61 carried the 314-cubic-inch V8 lineage into the 1920s on a longer 132-inch wheelbase. Their greater chassis length altered body proportions and provided room for the more substantial closed coachwork demanded after the war. A Type 59 or Type 61 body or chassis component is therefore not automatically suitable for the 125-inch Type 55.

Type 55 versus the V-63

The V-63 arrived after the Type 61 and incorporated major chassis advances, most notably four-wheel braking. That difference sharply separates the driving experience. A V-63 offers more braking capability for modern touring, while the Type 55 represents Cadillac's earlier rear-brake, First World War-era engineering practice.

Ownership and Restoration Notes

A Type 55 restoration is primarily a research and fabrication exercise. Routine consumables can often be adapted or manufactured, but unique castings, electrical housings, instruments, lamps, carburetor components, hubs, and body hardware may require years of searching. Type 57, Type 59, and Type 61 parts are useful references, not guaranteed substitutes.

Engine work demands a shop familiar with early separate-block V8 construction, long-stroke crankshafts, poured or period-style bearing practice where applicable, and the dimensional checks required before machining irreplaceable castings. Cooling passages should be inspected before final assembly. A cosmetic overhaul that leaves internal corrosion, blocked galleries, or a weak radiator untouched can ruin expensive engine work.

The gearbox and rear axle are durable when correctly assembled, but shafts, bearings, gears, bushings, and seals may need to be made rather than ordered. Clutch geometry and linkage adjustment deserve equal attention. Small errors can produce dragging, gear clash, or an engagement harsh enough to damage driveline components.

Closed bodies create the largest structural risk. Roof leaks feed hidden decay in sills, pillars, door frames, and joints, while sheet metal may remain outwardly presentable. Rebuilding the timber skeleton is cabinetmaking and structural engineering, not simply panel repair. Doors that sag or change fit when the chassis is jacked are a warning that the body structure is no longer carrying loads correctly.

Service should be based on frequent inspection rather than modern mileage intervals. Lubrication points, steering joints, spring shackles, wheel bearings, brake linkage, fluid levels, ignition contacts, tire condition, and spoke security all warrant attention before sustained road use.

Buyer and Inspection Points

A useful inspection separates identity, completeness, and operability. A running but heavily substituted car may be a poorer restoration candidate than a stationary, documented Type 55 retaining its correct castings and body hardware.

Prospective buyers should budget around what is absent, not merely what is broken. A damaged original component can often be rebuilt, documented, and retained. A missing Type 55-specific part may require pattern making, casting, machining, plating, and extensive historical research.

Collector and Market Relevance

Collectors value the Type 55 for three concrete attributes: its 1917 date, its place in Cadillac's first series-production V8 lineage, and the survival of correct chassis and coachwork details. Open touring cars are visually accessible and practical for group events, but an intact closed body can be substantially rarer because timber-framed sedans and limousines were difficult to preserve.

Desirability depends less on cosmetic shine than on identity and completeness. A documented original body, correct 314-cubic-inch engine, period electrical equipment, authentic instruments, and an unbroken ownership file usually carry more historical weight than a newly fabricated open body with modernized mechanical components.

Auction results can vary sharply because no two surviving cars have identical bodies, restoration histories, or levels of authenticity. The market distinguishes preserved cars, established older restorations, concours reconstructions, modified tourers, and speedster-bodied chassis. Treating all Type 55 sales as directly comparable obscures those differences.

Cultural and Historical Relevance

The Type 55 belongs to the period when the V8 changed from an exotic engine into a credible production choice for an American luxury manufacturer. Cadillac's earlier Dewar Trophy achievements had already linked the company with precision and interchangeability. The early V8 cars added smooth multi-cylinder power and an electrical system that reduced the physical effort of operating a large automobile.

There is no substantial factory motorsport program defining the Type 55, and it should not be assigned one retrospectively. Its modern culture centers on Horseless Carriage-era touring, Cadillac and LaSalle club scholarship, preservation judging, technical exchange, and the specialist craft needed to keep prewar machinery functional.

Period photographs of formal events, touring parties, institutions, and military transport give these cars a broader documentary value. Film and display use can make an altered example familiar to the public, but screen provenance does not replace factory provenance when a collector evaluates originality.

Frequently Asked Questions

What engine does the 1917 Cadillac Type 55 use?

It uses a naturally aspirated, water-cooled L-head V8 displacing approximately 314 cubic inches, or 5.15 liters. The bore is 3.125 inches, the stroke is 5.125 inches, and factory specifications commonly list 70 horsepower.

What is the difference between the Cadillac Type 55 and Type 57?

The Type 55 is the 1917 model, while the Type 57 succeeded it for 1918 and continued through 1919. Both belong to Cadillac's early 314-cubic-inch V8 lineage, but serial evidence, accessories, castings, chassis details, and coachwork should be checked against year-specific literature.

How can a genuine Type 55 be identified?

Identification requires agreement among chassis or serial markings, engine evidence, body numbers, data plates, title history, and period Cadillac records. The radiator, hood, or touring body alone is insufficient because bodies and mechanical parts have often been transferred.

Does matching numbers have the same meaning on a Type 55 as on a postwar Cadillac?

No. Early records do not always provide the comprehensive number documentation available for later collector cars. A credible original-engine claim should be supported by accepted serial sequences, physical correctness, period paperwork, and recognized marque expertise.

What are the major mechanical problems on a restored Type 55?

Cooling restriction, cracked or corroded castings, worn bearings, weak oil circulation, carburetor faults, ignition deterioration, clutch misadjustment, steering wear, and poorly equalized rear brakes are central concerns. Old tires, loose wheel spokes, and worn spring shackles can be equally serious.

Are parts available for the Cadillac Type 55 V8?

Service materials and some reproduction items are available through specialist networks, but many engine, electrical, instrument, wheel, and body components are scarce. Parts from Types 57, 59, and 61 may resemble Type 55 pieces without being dimensionally or historically correct.

What makes a Type 55 restoration expensive?

The largest costs arise from missing unique hardware, damaged V8 castings, crankshaft and bearing work, radiator reconstruction, electrical restoration, wheel rebuilding, and replacement of structural body timber. Research and pattern making can exceed the cost of ordinary mechanical labor.

Collector Takeaway

The 1917 Type 55 matters because it records the moment when Cadillac's V8 had moved beyond introduction and become normal production hardware. Its 314-cubic-inch side-valve engine, electric starting, familiar control arrangement, and broad body catalog show how quickly advanced engineering was being converted into a usable luxury car.

The best Type 55 is not necessarily the brightest one. It is the car whose chassis, engine, coachwork, controls, and paper trail agree, and whose restoration respects the limitations of rear-wheel brakes, timber body construction, and century-old castings. Preserve those facts and the Type 55 explains Cadillac's early V8 authority more convincingly than any modernized recreation can.