Sonett II
In the early 1960s, Saab's North American dealers managed to convince its management that a sports car would be a right choice to appeal to the US market as European sports cars, especially those from MG and Triumph were a huge success. The demands from the dealers included a targa top roof, wind-up windows, a heater as standard equipment and good handling. Saab decided to outsource the development of the project and two concept cars were built, the Saab MFI13 by Malmö Flygindustri which was designed by Björn Karlström, an aircraft and automotive illustrator, and Walter Kern,[9] an engineer at Massachusetts Institute of Technology, and the Saab Catherina by Sixten Sason in his private design studio. The management ultimately accepted the MFI13 design proposal.[10]
After some modifications, such as the adoption of a sheet metal box-frame chassis, the MFI13 was unveiled first at the 1966 New York Auto Show and the Geneva Motor Show. was put into limited production in 1966 as the Sonett II, manufactured at the Aktiebolaget Svenska Järnvägsverkstäderna (ASJ) in Arlöv. Inside Saab, it was designated model 97. A further 230 units were assembled in 1967, but as the two-stroke engine became increasingly uncompetitive in the US market due to emissions regulations, a switch to the Ford Taunus V4 engine was made in the middle of the 1967 production year, and the model was renamed the Sonett V4. Apart from the engine and related drivetrain, the Sonett II and Sonett V4 share much of their componentry and are distinguished from each other by a buldge on the hood of the V4, in order to accommodate the larger and taller engine.[11][12] The additional weight did require some strengthening of the chassis and suspension pieces, and the wheels were half an inch wider than the four-inch units used on the Sonett II.[13] The 1967 year holds the distinction of becoming the last 2 stroke engine passenger automobile sold new in the United States.[14]
Like the Sonett I prototype, the Sonett II's fiberglass body was bolted to a box-type chassis with an added roll-bar to support the hard top. The entire front hood section hinged forward to allow easy access to the engine, transmission, and front suspension. Equipped with a three-cylinder, two-stroke engine generating 60 PS, the Sonett II achieved 0 to 100 km/h (0–62 mph) time of 12.5 seconds, with a top speed of 150 km/h. All Sonett IIs were left hand drive (LHD).
Designed as a race car, the Sonett II competed successfully against other small European sports cars, including the Austin-Healey Sprite and Triumph Spitfire, in Sports Car Club of America (SCCA) races of the period. Due to low production volume, it was disqualified from certain competitions. By 1967, the two-stroke engine failed to meet US emission control standards.[15] In 2011 a two-stroke Sonett II achieved 109 mph at the Bonneville Salt Flats.[16] Of the 28 Sonett IIs manufactured in 1966 all were equipped with 841 cc three cylinder two-stroke engines. SAAB produced serial numbers 29 through 258 with the two-stroke engine, serial number 259 was the first Sonett to have the V4 engine.
All Sonett II transmissions had a freewheel that could be engaged and disengaged while in motion via a pull handle down near the throttle pedal. The freewheel was required in the normal (non-oil pump engines) SAAB two stroke engines but not in the racing engines that had an oil injection system fed from a supply tank, nor in the Sonett V4 since it had a four-stroke engine with the common recirculating pressure lubrication.
The Škoda-engined ÚVMV 1100 GT was based on the Sonett II.
Sonett V4
When Saab started using the Ford Taunus V4 engine in their 95, 96, and Monte Carlo models, an upgrade for the low-volume Sonett II became economically feasible. The Sonett V4 was introduced with a 1498 cc Ford V4 engine in the middle of the 1967 model year starting with serial number 259. A new "bulge" hood, designed by Gunnar A. Sjögren, was required to clear the larger V4 engine, with a slight right offset to avoid obstructing the driver's view. This asymmetrical hood shape, criticized by both the automotive press and within Saab itself, contributed to the motivation for the 1970 Sonett III redesign.[12]
The Ford V4 engine produced 65 hp, and—combined with the car's lightweight chassis and fiberglass construction—allowed the V4 model to accelerate from 0 to 100 km/h (0 to 62 mph) in 12.5 seconds, with a top speed of 160 km/h. The V4's dashboard was wrinkle finished black, unlike the wooden panel used in the Sonett II.[13]
Following the low-volume 1966–67 Sonett IIs, Saab ramped up Sonett V4 production to meet minimum SCCA requirements, assembling 70 units in the 1967 transition year, 900 units in 1968, and 640 units in the final 1969 production year—a total of 1,610 cars. The 1969 models can be recognized by their taller seat backs and by having a lid for the glove compartment, while the heater was also made somewhat more efficient.[1]