I was just wondering if coil overs can be put on a calibra...i`ve seen a white astra with coil overs on the front...i guess its someone from here, but the rear should be possible no? I mean the calibra rear is quite similar to a bmw e36, as standard they have a small spring between the trailing arm and the body, but a the coil overs replace the origional damper but with a spring on it......those new bilstiens look yummy!!
The problem with coil-over suspension on rear beam vauxhalls is that the springs are reloacated over the dampers (obviously). Just that the original suspension turrets are not load bearing structures (and can be too small). So you have to strengthen them (and maybe enlarge them).
I would think with IRS this would be less of a problem so it could be done.