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Sunbeam 1.0 LS

   Initially three engines were available. It's bigger brothers had a 1.3 or a 1.6 litre engine, the Avenger cast-iron units. Later on there was the 2.0 litre Sunbeam Lotus.

The Sunbeam 1.0 LS first appeared in 1977. Chrysler UK had received assistance from the British Government in 1976 to develop a new small car to replace the Imp. Chrysler called it Project 424.
The modest version of the Chrysler Sunbeam had a further developed version of the Imp engine: light alloy, 928cc. They had increased its capacity from 875 to 930 as it was heavier than an Imp. However the power was still the same as the cylinder head was not as good as the Imp one.

This 1.0 LS was the replacer of the Imp and as such produced in Linwood. It most certainly did not look or handle like an Imp. It was a rear wheel drive car with the engine in front, mounted upright. Based on the Avenger, it was quite a bit larger than the Imp. It was built on the essentially the same floorpan as the Avenger. It did retain some Imp features and styling cues. The hatchback at least was in the spirit of Imp.

Chrysler wanted to use the Sunbeam name, because of its reputation for speed and spectacle. However, it was also their policy to let the Rootes marques fade into history. The compromise was the use of Sunbeam as a type not a marque. Hence: Chrysler Sunbeam (later Talbot Sunbeam).

The Chrysler Sunbeam 1.0 LS had a different gearbox/clutch fitted. It had a different flywheel and a different starter motor.

928 cc875 cc Imp block
Castingthere's an engine mount on either side of the block
Timing coverthere's an engine mount there
Sumpthe engine stands uprightthe engine stands at an angle of 45°
Tappet coverthe engine stands uprightthe engine stands at an angle of 45°
Bore x Strokebore is 2mm larger
Compression Ratio9:110:1
Max. power± 41 DIN hp @ 5000rpm± 39 DIN hp @ 5000rpm
Torque52 lbs.ft. @2600rpm52 lbs.ft @ 2800rpm (WSM)
Flywheelflywheel end has an oil seal;
held with 6 bolts
larger hole in the flywheel;
held with 4 bolts and a dowel
Startermotorsame as the 1.3 or 1.6 model, with a built-in starter relaybendix
Thermostat &
Temperature sensor
in the waterpumpat the end of the cylinder head


A year later, in 1978, Chrysler sold its European stock to Peugeot. The Linwood plant closed down in 1981, ending Sunbeam and Avenger production.

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