Back in 2005 I posted on this subject on the "Damper Histograms" thread. John Bucknell was kind enough back then to post on that thread some images that I sent him. I repost part of John's post here to show that nothing much has changed. (See also the current "Roll Rates in RCVD" thread for more of "nothing much has changed".)

The deep lack of understanding of how these things work is evident in the images below that are taken from various VD/Suspension Design textbooks (and the notes I made when I first read them ). The lack of understanding of how to calculate modal-spring-rates is seen in the 2CV image. Tim's comments about how "it's just toooo haaaaard to package..." is seen to be utter nonsense from the BLMC images (the interconnecting hydraulic pipe is about the size of brake line). The lack of understanding of Z-bar ERMD is evident in the Olley book (compare with original Packard picture above).

BTW, I had one of the BMC cars, and it rode well over bumps and cornered very flat. The "big-picture" engineering was very well done. However, the company went down the crapper, NOT because of the suspension, but because of pathetic detail design (similar to that seen in a lot of FSAE, especially English and Indian!), totally incompetent Top-Level management, and a lazy, unionised, and militant workforce.

The following is cut-and-pasted from John's 2005 post:
~~~~~o0o~~~~~


"Citroen 2CV and BMC, from "New Directions in Suspension Design", Colin Cambell, 1981 (with some comments by Z)


Packard, from "Chassis Design...", based on notes by Maurice Olley, pre-1960? (with more comments...)


Z-bar sketches by Z"

Z