Chapman strut

[2] This rear-engined car used swing axle independent rear suspension, with long near-vertical coilover struts from high mounting points on the space frame chassis.

MacPherson's strut took advantage of the unitary car bodies appearing in new factories after World War II: the strut requires a high top mounting point, which would be difficult to arrange for a ladder chassis, but is also advantageous for unitary construction as it distributes suspension loads over a greater volume of the bodyshell.

[6] MacPherson's strut was cheap to manufacture and reliable in service, having few moving joints and using the new telescopic shock absorbers, rather than the previous lever arms.

[7] The MacPherson strut appears to have had little influence on Chapman at this time (although he would later use it unsuccessfully for the front suspension of his Lotus 17).

At a 750 Motor Club meeting in 1957, Chapman saw the Goggomobil system and was impressed by its Lotus-like simplicity and light weight.

Chapman also avoided the swing axle and its camber changes with suspension travel, in favour of a drive shaft with two universal joints.

[12] The connection between the hub carrier and the shock absorber base was made rigid, making the spring unit into a strut and also controlling the camber angle.

Chapman struts, and their wide separation of load paths into the chassis, were a good fit to a stressed-skin structure such as the Elite and may have been an influence on its choice.

[12] They were less appropriate for a backbone chassis, requiring broad outriggers to carry the strut top loads, an un-Chapman-like feature that added weight for only a single purpose and was difficult to make stiff enough.

[19] It has been suggested that the spring forces from these struts would have been better supported as torsion bars, which could then have been anchored to the main suspension spine.

Owing to the need to isolate the engine and transaxle from the chassis in order to reduce noise and vibration, the rubber mounts led to an excessive sideways movement of the driveshafts.

The successful mid-engined Lotus 18 of 1960 no longer had the high bodywork behind the driver's seat on which to mount the tops of the struts.