Coil Over Comment In Feb 04 Volks World Mag

I looked into the technical details more of the 944 conversion and found little on the web but one kit did state, "the rear coil-over conversion is to be used in conjuction with the tornsion bars".

If it's the bolt that seems to be the weak point then, as MattKab pointed out, then it should be upgraded and as Alex said the design has proved itself well in off road racing applications.