Quite a while ago I advised Morgan directors in a technical report on Morgan suspensions that their Watt's linkage had the links at the wrong angle, they must be horizontal not as in the CAD image. I guess they would already have had their doubts as soon as they bounced the car though. I was then told that there was no room left for a Panhard underneath across the chassis to replace the Watt's where it should be, so they had to put it high up and diagonal as on the AR6 - seen that beast twitch (yaw?) on full power changes then on the track, wonder why that is then?
I would not put a Panhard rod at anything other than straight across the chassis, as besides other effects, lateral loads on the axle (cornering) will put fore/aft loads into the axle too. Also consider single wheel inputs - left wheel will follow a path that is in pretty well a vertical plane, the right wheel will not, it will arc about the left wheel. OK may be trivial and may not affect things in practice, but the Panhard rod should be where a Panhard rod should be to give the right restraint. The packaging is tight, we know, but it is possible.
I leave it to you to guess where the Panhard is on the 5L.
Suspension design is forever a matter of compromises (as is life they say?) each to their own, some things that should not work do quite well, look at the ridiculously high roll centre on F1 cars. We have ours below ground level and goes even lower as people modify to get negative camber etc etc. What is ideal? That's all - late now - Peter.
