Back to the rear arms fouling on the chassis. I took some pictures & measurements and am not convincved there is a problem.
(there are pant chip marks on the chassis rails and arms but I do not know if that was caused by driving or by letting the axle reast on the chassis rails).

Some photos to tell the story. (driver's side, petrol tank on the right)

Lower arm's position when the axle is hanging in the air (it is not resting on the block off wood)

rear arms - no load

Same but with the weight of the car on that corner (jacked up axle on that side until the body was just off the stand). Notice the slight change of angle. Different in hieght seems to be tiny, not more than 10 mm for sure.

rear arms - loaded

Now this shows the lower rear arm resting on the chassis rail that run across the back.

arm resting

and with a tape measure. There is at least 50 mm of movement before the arm contacts the rails. (axle is unsupported so when car is on the road, it would sit even higher).

arms droop


Can there be that much reserve movement since the shocks are bottomed out already i.e. the spring is at its maximum extension? (unless there is a rubber bump stop or another spring inside) but I'd find it hard to believe there is another 50 mm of movement avaialble.

So how do I work out what is the maximum droop of my rear suspension?

(shocks are triumph dolomite)

[Edited on 26/9/06 by 02GF74]

Looks like you have no danger of the axle hitting the chassis. With the car jacked up there should be no "reserve" movement left, unless the shocks are binding for some reason (e.g. bent or rusty damper rod ).

However, it does seem like the springs are maybe a little too stiff. The spring compression when you put the weight on the axle seems to be very small. This could be causing "topping out" which is the opposite of bottoming out, i.e. the dampers are regularly reaching their maximum extension over small dips on the road, which could also be causing clonking and will likely make the shocks start leaking prematurely.