Saab Sonett

Saab Sonett at a glance

The Sonett is one of the less common chapters in our Saab history; the rest of the range is in our Saab catalogue, and other sports cars of the period are in our classic cars section.

Sonett I: an aircraft maker's lightweight roadster

The first Sonett was built on a budget of SEK 75,000 and shown at the Stockholm motor show on 16 March 1956 as the Saab 94. Its riveted aluminium chassis weighed under 70 kg, and the glass-reinforced plastic body came from Soab of Gothenburg. The engine was a 748 cc three-cylinder two-stroke from the Saab 93, the successor of Saab's first car, the 92, tuned to 42 kW (57.5 PS), and turned round so that it sat behind the gearbox while still driving the front wheels.

The whole car weighed 600 kg, and Saab projected a top speed of 190 km/h. A run of 2,000 cars was planned for 1957 and later abandoned. Only six were built, between 1955 and early 1957, all with right-hand drive, and all six survive. Decades later, in September 1996, Erik Carlsson drove prototype number one to a Swedish record for cars under 750 cc at 159.4 km/h.

Sonett II and Sonett V4: from two-stroke to Ford power

Saab returned to the idea in the mid-1960s. The Sonett II grew out of the MFI 13, a design by Björn Karlström developed by Malmö Flygindustri, and was assembled by ASJ (Aktiebolaget Svenska Järnvägsverkstäderna) at Arlöv. It had a sheet steel frame with an integrated roll bar, a fibreglass coupé body and the 841 cc two-stroke from the 96 Monte Carlo, here with 44 kW (60 PS). Wikipedia gives 0-100 km/h in 12.5 seconds and 150 km/h; 28 cars were built in 1966 and 230 in 1967.

The two-stroke was already out of step with US emissions rules, and Saab's most important market for the car was America. Car number 259 was the first Sonett with the 1,498 cc Ford Taunus V4 of 48 kW (65 hp). The taller engine needed a bulge in the bonnet, drawn by Gunnar A. Sjögren, and the wheels grew half an inch wider than the Sonett II's four-inch rims. Top speed rose to 160 km/h. Saab built 70 V4 cars in 1967, 900 in 1968 and 640 in 1969, nearly all for export to the United States, where they sold for USD 3,200 to 3,800.

Figures from Wikipedia EN. The Saab Network quotes 1,868 cars for the second-generation coupés, which matches the 258 two-strokes and 1,610 V4s combined. Sources date the 1.7-litre engine to 1971 or 1972.

Sonett III: Italian lines on a carried-over centre

For 1970 Saab wanted a more modern shape without the cost of a new floorpan. The Turin designer Sergio Coggiola produced the first proposal for a new nose and tail, and Gunnar A. Sjögren adapted and toned it down to fit the existing centre section. The result was a wedge-shaped coupé with a drag coefficient of 0.31, slightly heavier than the Sonett II. Saab unveiled it at the New York Auto Show in 1970 in standard form, with steel wheels and brown corduroy trim, and as a luxury version with alloy wheels and leather.

The Sonett III used the 1,498 cc V4 at first, then from 1971 the 1,698 cc version. Lower compression to meet emissions rules meant the bigger engine still gave 48 kW (65 hp). Saab fitted a lower 42:9 final drive than the 96's 39:8, and Wikipedia lists 0-100 km/h in 13 seconds and 165 km/h; Hagerty UK quotes 106 mph (171 km/h). US dealers could fit air conditioning, and from 1973 the car carried large impact bumpers to meet American rules.

The Sonett III was the best-selling Sonett, with 8,368 cars, and there were no official UK exports. Sales were still disappointing, and the 1973 oil crisis made a small two-seater an even harder sell. Production ended in late 1974; the last car, a bright yellow Sonett III built at Arlöv, is kept at the Saab museum in Trollhättan.

Saab Sonett today: what to check when buying

The fibreglass body cannot rot, so attention goes to the sheet steel frame beneath it: inspect it from below, around the suspension mounts and wherever water can collect. Fibreglass can crack, so look for stress cracks and poorly repaired accident damage in the panels.

The V4 shares its weak points with the Saab 96: Hagerty UK warns that the fibre balance shaft gear can wear and cause vibration, that a rumbling bottom end points to tired main bearings, and that the cooling system and water pump need checking when hot. Many Sonetts have had a later 1.7-litre V4 fitted for more power, and Hagerty notes that such swaps have not hurt resale. Two-stroke Sonett IIs are the rarest and need the right fuel and oil mixture. Engine and running gear parts are shared with the 96 and 95, which keeps mechanical repairs manageable; body and trim parts are much harder to find.

Values from dated Hagerty data:

• Sonett III in good condition: about EUR 10,700 (USD 11,100), Hagerty valuation tool, January 2025.
• In July 2019 Hagerty valued excellent (#2) cars at USD 23,800 for a Sonett II two-stroke, USD 17,300 for a Sonett V4 and USD 10,300 for a Sonett III, about EUR 21,200, 15,400 and 9,200 at that time.

In Hagerty's figures the rare two-stroke cars cost the most, and the Sonett III is the affordable way into the family.