Saab Sonett

Saab Automobile

Industry	Automotive
Founded	April 1, 1945 (1945-04-01) in Trollhättan, Sweden
Headquarters	Trollhättan , Sweden
Products	Saab Sonett (sports car)

The Saab Sonett is a vehicle produced by the Swedish manufacturer Saab Automobile during two distinct periods: from 1955 to 1957 and later from 1966 until 1974. Its powertrains and many mechanical parts were shared with contemporary models such as the Saab 93, Saab 95, and Saab 96. Primarily designed for export to the lucrative American market, the Sonett was only sporadically available in Sweden during the 1968 and 1972 model years.

The initial prototype, commonly referred to as the Sonett I, was a lightweight, two-seat open-top roadster racer. A decade later, Saab resurrected the Sonett name for its production versions: II, V4, and III.

Sonett I

During the mid-1950s, Rolf Mellde, an engine developer at Saab and motorsport enthusiast, collaborated with Lars Olov Olsson, Olle Lindkvist, and Gotta Svensson to conceive a two-seat roadster prototype. This project took place in a barn located in Åsaka near Trollhättan, where Saab's primary manufacturing plant is situated. The limited research initiative had a modest budget of approximately kr 75,000 and was initially named Saab 94 before being rebranded as the Sonett. The designation "Sonett" originates from the Swedish phrase "Så nätt den är", translating roughly to "how neat it is," a term coined by designer Sixten Sason. Although initially declined by Saab’s executives, the name gained approval in October 1955 upon completion of the first prototype.

The Sonett I incorporated numerous components from the Saab 93 sedan, including its front suspension, engine, and gearbox. Notably, both engine and transmission were rotated 180 degrees and positioned behind the front axle. This configuration necessitated reversing the engine's rotational direction—a task simplified by its two-stroke design.

Rather than adopting a tubular frame chassis common among contemporary low-volume sports cars, Mellde opted for an innovative stressed skin aluminium chassis weighing under 70 kg (150 lb). The chassis sections were riveted together using techniques borrowed from aircraft manufacturing. Key mechanical parts such as the engine, fuel tank, axles, and body panels were mounted directly onto this chassis. Mellde and Sason also chose glass-reinforced plastic for the car’s bodywork—a material gaining popularity in automotive circles at that time. To fabricate this lightweight body shell, Saab contracted Soab, a Swedish plastics firm based in Gothenburg with expertise in American-imported materials.

The Sonett made its debut on 16 March 1956 at Stockholm’s Bilsalong motor show. Powered by a three-cylinder 748 cc two-stroke engine producing approximately 57.5 PS (42.3 kW), it was an advanced racer weighing close to 600 kilograms (1,300 lb), drawing inspiration from aircraft engineering principles.

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Rear view of Saab Sonett I

With an anticipated maximum speed near 120 mph (190 km/h), the Sonett I was poised to perform well on European racing circuits. Plans called for a production volume of around 2,000 units in 1957; however, changes in racing regulations allowing modified production vehicles into classes targeted by the Sonett diminished its competitive edge and commercial appeal.

Only six examples were produced between 1955 and early 1957—all equipped with right-hand drive. By early 1958, Saab management abandoned further development of the Sonett I in favor of creating a sportier version of the Saab 93 sedan known as the GT 750. The original prototype "No.1," crafted with a hand-built fiberglass body, served as the blueprint for subsequent units. Today, this model is extremely rare—only two are known to remain in the United States. Chassis number two was once part of General Motors’ Heritage Center collection but was transferred to Saab Cars North America following GM's bankruptcy in 2009. After Saab's own bankruptcy in 2012, it became part of the Saab Heritage Car Museum USA located in South Dakota.

In September 1996, rally driver Erik Carlsson set a new Swedish speed record for vehicles with engines under 750 cc by reaching 159.4 km/h (99.0 mph) in the restored original Sonett I prototype "No.1".

Sonett II

During the early 1960s, Saab's North American dealers persuaded company leadership that launching a sports car would effectively capture the US market, where European brands like MG and Triumph were enjoying significant success. The dealers specified features such as a targa top roof, roll-up windows, standard heating, and excellent handling characteristics. Saab opted to outsource the development, resulting in two concept vehicles: the Saab MFI13, created by Malmö Flygindustri with design input from Björn Karlström—an illustrator specializing in aircraft and automobiles—and MIT engineer Walter Kern, alongside the Saab Catherina, designed privately by Sixten Sason. Ultimately, management approved the MFI13 design.

Following adjustments—including the implementation of a sheet metal box-frame chassis—the MFI13 debuted at the 1966 New York Auto Show and the Geneva Motor Show. Production commenced later that year with the model named Sonett II, assembled at Aktiebolaget Svenska Järnvägsverkstäderna (ASJ) in Arlöv. Internally, it was known as model 97. In 1967, approximately 230 units were produced; however, tightening US emissions regulations rendered the two-stroke engine increasingly obsolete. Consequently, mid-1967 production saw a transition to the Ford Taunus V4 engine, prompting a rebranding as the Sonett V4. Aside from the powertrain differences, both Sonett II and V4 models shared much of their construction. The V4 featured a distinctive hood bulge to house its larger engine. To accommodate the increased weight, chassis and suspension components were reinforced, and wheels were widened by half an inch compared to the four-inch rims used on the original Sonett II. Notably, 1967 marked the final year that a two-stroke engine passenger vehicle was sold new in the United States.

Mirroring its predecessor prototype, the Sonett II utilized a fiberglass body affixed to a box-type frame chassis reinforced with a roll-bar supporting the hardtop. The entire front hood pivoted forward for straightforward access to mechanical components including the engine, transmission, and front suspension. Powered by an 841 cc three-cylinder two-stroke engine producing 60 metric horsepower (44 kW), it could accelerate from zero to 100 km/h (0–62 mph) in approximately 12.5 seconds and reach a maximum speed of 150 kilometres per hour (93 mph). All Sonett IIs were configured for left-hand drive.

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Rear view of a 1966 two-stroke Sonett II

Engineered with racing intentions, the Sonett II achieved competitive results against other compact European sports cars such as the Austin-Healey Sprite and Triumph Spitfire in Sports Car Club of America (SCCA) events during its era.Template:Fix/category However, low production numbers led to disqualification from certain contests. By 1967, US emissions standards rendered its two-stroke engine noncompliant. Remarkably, in 2011 a two-stroke Sonett II attained a speed of 109 at the Bonneville Salt Flats. Of all units produced in 1966—totaling 28—each featured an 841 cc three-cylinder two-stroke engine. Serial numbers from 29 to 258 also used this powerplant; serial number 259 marked the first equipped with the V4 engine.

Every Sonett II transmission incorporated a freewheel mechanism operable via a pull handle near the accelerator pedal while driving. This device was essential for standard SAAB two-stroke engines lacking oil pumps but was unnecessary for racing variants equipped with oil injection systems supplied from dedicated tanks or for the Sonett V4's four-stroke engine featuring conventional recirculating pressure lubrication.

The Škoda-powered ÚVMV 1100 GT drew its design inspiration from the Sonett II platform.

Sonett V4

File:1968 SAAB Sonett V4.jpg

1968 SAAB Sonett V4

Saab's adoption of the Ford Taunus V4 engine in models such as the 95, 96, and Monte Carlo enabled a cost-effective upgrade for the limited-production Sonett II. Introduced midway through the 1967 model year at serial number 259, the Sonett V4 featured a 1.5 L (1,498 cc) Ford V4 engine mounted centrally. To accommodate the larger engine, a new "bulge" hood was designed by Gunnar A. Sjögren, incorporating a slight offset to the right to maintain driver visibility. This asymmetrical hood design received criticism from automotive journalists and within Saab itself, influencing the comprehensive redesign seen in the 1970 Sonett III.

The Ford V4 delivered 65 hp (48 kW), and when paired with the vehicle’s lightweight frame and fiberglass body, enabled acceleration from 0 to 100 km/h (0 to 62 mph) in 12.5 seconds, reaching a maximum speed of 160 km/h (99 mph). Unlike the wooden dashboard panel found in the Sonett II, the V4 model featured a black wrinkle-finished dashboard.

Following the limited production run of Sonett IIs in 1966–67, Saab increased output of the Sonett V4 to satisfy SCCA minimum production requirements. This resulted in 70 units produced during the 1967 transition year, followed by 900 units in 1968 and 640 units in 1969, totaling 1,610 vehicles. The 1969 versions are identifiable by their taller seatbacks and inclusion of a glove compartment lid, alongside improvements to heater efficiency.

Although assembled in Sweden, almost all Sonett V4s were exported to the United States, with an original MSRP ranging from US$3,200 to US$3,800 (equivalent to approximately US$Template:Inflation to US$Template:Inflation today). Beyond its distinctive fiberglass exterior, the Sonett V4 incorporated advanced safety elements for its era, such as a roll bar, three-point seat belts, and high-backed bucket seats designed to reduce whiplash injuries. Notably different from typical American sports cars like the Chevrolet Corvette, it featured front-wheel drive, an automatic freewheeling clutch disengaging when off throttle, and a column-mounted shifter rather than a conventional floor-mounted gear lever.

Despite modest marketing efforts by Saab and its unconventional characteristics and styling, the Sonett V4 secured a dedicated following in the US market, largely driven by successful SCCA racing campaigns with the earlier Sonett II. Its main rivals included British sports cars such as the MG Midget, MG MGB, Triumph TR5, TVR Grantura, and Austin-Healey Sprite Mark IV.

The enactment of the Clean Air Act in 1970 necessitated changes to the Ford V4’s emission control system that proved incompatible with the existing Sonett II/V4 body design, prompting Saab to develop the redesigned Sonett III.

Sonett III

In 1970, the Sonett V4 underwent a redesign and was rebranded as the Sonett III. Initially, the Italian designer Sergio Coggiola was commissioned to enhance the car's aesthetics, addressing the widespread criticism of the Sonett II's styling. Nevertheless, Saab assigned its in-house designer, Gunnar A. Sjögren, to adapt the new look to the existing Sonett II chassis, avoiding costly modifications to the production line. The rear compartment hatch door from the Sonett II/V4 was replaced by a hinged rear window glass. To comply with a directive for a smooth hood without protrusions, the engine bay access was modified into a small front pop-up panel, which limited engine accessibility compared to the Sonett V4. Major engine maintenance necessitated removing the entire front hood section.

File:Saab Sonett III Cockpit.jpg

1972 Saab Sonett III dashboard

To better suit American consumer preferences, the Sonett III featured a floor-mounted gear lever rather than the column shifter found in the Sonett V4, along with optional dealer-installed air conditioning. The car retained manually operated hidden headlamps controlled by a lever. Following US safety mandates introduced after 1972, low-speed impact-resistant bumpers were added, which significantly altered its Italian-inspired design. All Sonett III models produced were equipped with left-hand drive.

The original 1500 cc Ford Taunus V4 engine continued to power the 1970 and 1971 models; however, emissions regulations led to reduced horsepower during those years. From 1972 through 1974, a 1700 cc Ford V4 engine was installed, but due to increasingly stringent federal standards, its net output remained at 65 horsepower (48 kW), matching that of the smaller displacement engine. Despite this, the Sonett III could accelerate from 0 to 100 km/h (62 mph) in approximately 13 seconds. Its differential gear ratio was higher—42 teeth on the ring gear paired with 9 teeth on the pinion—compared to the standard transmission ratio of models 95/96 (39:8), enabling a top speed of about 165 km/h (103 mph). This performance was also supported by an aerodynamic drag coefficient of 0.31 cd.

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Rear view of a 1972 Saab Sonett III in green

Sales figures declined sharply during the 1973 oil crisis, prompting Saab to cease production late in 1974. Throughout its production run from 1970 to 1974, a total of 8,368 units of the Sonett III were built.

By that time, cumulative production across all Sonett variants—Sonett II, Sonett V4, and Sonett III—had reached 10,236 vehicles.

During this period, Jonas Kjellberg, president of Saab USA, explored developing a new generation of the Sonett through a partnership with Reliant Motors and styling by Tom Karen of Ogle Design. The plan involved Reliant handling design, engineering, and assembly for the US market. However, this initiative was terminated after Saab's board rejected Reliant's business proposal when Kjellberg presented it.

Additionally, Saab experimented with equipping the Sonett III with a Rankine cycle steam engine for test purposes. One such experimental vehicle has survived and appeared at auction in Stockholm in July 2019.

Cancelled PhoeniX Concept

The Sonett designation was intended to make a comeback as the production model derived from the Saab PhoeniX concept.Template:Fix/category Crafted by designer Jason Castriota, this vehicle was envisioned as an accessible halo car for Saab. It was planned to be a 2+2 sports coupe capable of delivering up to 400 hp in its top configuration. The car would have been built on the new Phoenix platform, which was also set to support the upcoming generations of the 9-3 and 9-1 compact models. However, these initiatives were discontinued following Saab's closure in 2012.

External links

• Saab Sonett Super Sport