[rdorman]

I want to be clear about this before I begin. Jag makes a nice independent rear suspension. Is it perfect, no. But then what is.

In looking at the pictures of the suspension with the watts linkage I have nothiced that all of the attachement points are in single and not double shear. This is BAD. bolts are tension fastners and not sheer pastners. If a bolt is to be used, it should be in double shear. Use a good washer of sufficient hardness between bolt head and all moving, bearing surfaces.

Since you may be stuck with single shear bolts, this is about all I can think of to do. Use aircraft bolts of say 380,000 tensile strength or better. Not aircraft type, the real NAS etc type bolts. Use the appropriate ( size and strength ) washers and lock nuts ( if needed. Use anti-seeze and torque to the correct foot pounds for the bolt in use ( ask the dealer where you get them, locktight will also be OK, no need for the high temp stuff for these bolts ). The bolt holes must fit very closely. This include the one in the heim joints. Slop here will cause problems. There must be NO threads in the bearing area. Plus the unthreaded area should protrude at least half the diameter of the bolt into the hub carrier ( from the picture it appeared that this was where the threads where housed ).

Also, check you suspendion for bind in full bumb or droop. You dont want the watts linkage in this car to be the limiting factor. Unless the suspension has some sort of strap or something I am not seeing the bumb and droop travel is probably limited first by the shock.

In looking at the picture from the link above...I may be showing my ignorance here about jag rear end but it seems to me to a flawed design for high horsepower cars. The idea of uses the half shaft as effectivity an upper location support is ludicrous. Add compression and tension stresses to an allready highly stressed member in torsion. This must be one heavy half shaft!

I have seen some jag suspension correctly ( at least in my humble opinion ) modified with a new hub carrier ( FLOATING half shafts, At least out board ) that have four locating rods ( A arms, etc ) attached to the frame at four points. I seem to recall one that had five which may reduce the stress put on the connecting members but I can think of a few problems that might be run into with this.

Happy motoring.