Test report DS 8962 BX 78 — page 3: measurements on disconnected anti-roll links

In this document

This sheet, bearing the header STé AME A. CITROËN and numbered "PAGE N° 3" p. 13, continues a series of tests on the DS 8962 BX 78, mounted on trestles and devoid of front shock absorbers. Three successive configurations are tested, all with the 4 steering ball joints disconnected and the 2 transmissions disconnected but carried by the car.

First configuration

Left-side anti-roll link disconnected, right-side link connected. A series of recorded measurements (values 84/81.2; 84/81.5; 84/81; 84/80.5; 84/81; 84/81.5, with a second column around 2.5 to 3.5) gives a handwritten average of 2.92 p. 13.

Second configuration

Right-side anti-roll link disconnected, left-side connected and mounted with 2 spring-loaded ball joints tightened to 2 mKg then loosened by 1/8 of a turn. The measurements (around 85/80.2, second column close to 4.8-5.3) give an average of 4.9 p. 13.

Third configuration

Symmetrical configuration to the previous one: left-side anti-roll link disconnected, right-side connected and mounted with the same 2 spring-loaded ball joints (tightened to 2 mKg, loosened by 1/8 of a turn). The measurements (85/80.5 and 85/80.2, second column 4.5 to 4.8) give an average of 4.56 p. 13.

Each series is grouped by a handwritten brace linking the values to their average. A handwritten annotation "MODIF." appears at the bottom of the page, as well as the print reference "5-53 - L - 12.000" and "1 A4 -2" p. 13. The document continues (".../").

Context

The DS, presented by Citroën in 1955, is distinguished by its hydropneumatic suspension, designed under the direction of Paul Magès. The anti-roll links and steering ball joints are ground-linkage components whose behavior—play, friction, resistance—directly influences comfort and road holding.

This type of test on trestles, in a laboratory or test workshop, likely aimed to isolate the effect of each component (link, spring-loaded ball joint) by disconnecting it in turn, a classic method of mechanical fine-tuning during the development of the DS.

Archivist's perspective

This sheet follows a previous page of the same report (measurements car on wheels without front shock absorber), confirming that it is a continuous series of methodical tests on this test vehicle.

The three configurations compared here—left link alone disconnected, then right, with or without adjustment of the spring-loaded ball joints—seem to seek to quantify the isolated influence of each linkage on a measured quantity not identified in the document (likely friction or travel, to be compared with friction tests of front suspension components conducted elsewhere, cf. Dascotte report of 23 April 1958).

The rigor of the protocol—multiple repetitions, calculation of hand-annotated averages—illustrates the care taken by Magès' teams in the objectification of suspension settings, in a period when several solutions (air, hydropneumatic) were still being compared.