I can't speak for all of the venders. I know that Rob Grady has a higher tensile strength bolt and nut he recomends. Also way back in old Delorean Worlds there was a vender pushing a bracket that he claimed "improved" the system and prevented bending or breaking the TAB. I have to agree with a post that mentioned getting a harder and stronger bolt may mean that instead of a gradual failure it would just shear off when pushed to it's limit. (Being harder it also means brittler). Replacing the rubber pivot bushing with a less compliant ureathane may help improve handling but at the cost of more noise and vibration being transmitted into the frame. If this is a way to go then you must make the metal tube (spacer) inside strong enough (thick enough) to withstand the higher compressive stresses. You will also need hardened shims (washers) so they aren't squished. A heim joint would have the advantage of no preload so when you twist the joint it isn't trying so hard to return to it's neutral position. A ureathane joint made so the ureathane can swivel around the metal spacer could do the same thing. On many older cars there are venders that sell urathane bushings to upgrade the suspension (take alot of the looseness and compiance out) to improve handling and stiffen up the steering and suspension. Ureathane is also less prone to aging and damage from oil and gas. In all cases it makes the ride harsher (stiffer) but more responsive. BTW the workshop manual calls for 55 ft/lbs see K:08:02-K:09:01. In some cases torque values are not created so much for the fastener as for the components you are trying to fasten together. I think in this case the limiting factor is the metal spacer tube in the pivot bushing. In most cases unless specifically called out torque values are for CLEAN, DRY threads. When using bolts and nuts close to their yield point or a critical fastener it is never a good idea to reuse (retorque) more than a minimum # of times. Every time you torque a bolt and nut you stretch them a little. After too many cycles you will just pull it apart or rip the threads out of the nut. On many of the newer cars where many bolts and nuts are tightened to high levels the manuals warn you not to reuse the fastener. (Another reason to refer to the manual for the specific car you work on!)BTW how often have you ever seen mechanics use a CALIBRATED (in the last 10 years at least) torque wrench on suspension fasteners outside of wheel lugs! There is much more variation in torque then you think! David Teitelbaum vin 10757