Paris–Clermont road test of 20 May 1949 — suspension setting J

In this document

This sheet dated 20 May 1949 reports on a road test carried out on the Paris - Clermont route, concerning a "J" setting of the hydraulic suspension, specified by technical values: "FRONT 3rd hole" and "REAR Ø = 19.8" p. 79.

Passenger impressions

Two testimonies are recorded:

• Mr. B judges this setting "more tired than in the previous trip", in reference to a previous setting noted "A" p. 79.
• Mrs. B. describes a "first impression of insecurity", followed by habituation "in less than 80 km". She notes a "big difference in comfort compared to PVL.6", would like "greater damping", and points out a "noticeable windshield displacement" p. 79.

The document also bears a handwritten annotation repeating the date "20.5.49" in the top right corner p. 79.

Context

At the end of the 1940s, Paul Magès' teams at Citroën conducted numerous comparative road tests to refine the settings of the future hydropneumatic suspension, which would equip the Traction Avant and then, in 1955, the DS. The mention "PVL.6" likely designates a prototype or reference vehicle used for comfort comparisons — a common practice in development tests of the time, where several test cars coexisted under internal designations.

This type of report, sober and factual, corresponds to the empirical development method in force at the time: a parameter was varied (here the "J" setting), a given distance was covered, and the subjective impressions of the occupants were collected to guide subsequent adjustments.

Archivist's perspective

This short sheet illustrates well the iterative approach of Paul Magès: each test is identified by a setting letter (here "J", after an "A" setting mentioned in comparison), proof of a series of successive tests of which this is only one link p. 79.

The contrast between the two feelings — fatigue for one, initial insecurity then habituation for the other — shows the attention paid to individual perceptions, essential for calibrating a system intended to provide comfort superior to the average suspensions of the time.

This document likely finds its place in a series of comparable tests, to be compared with the BEA 1945 work programmes: suspension tests, launchers and Fressard works, which already mentions the organization of suspension tests within the design office.