When we first started running the 105 on the track the suspension, like everything else, was totally stock standard.  In this condition the car would often behave very unpredictably  when pushed hard, the worst of the problems being

The Axle tramping is due to the pore lateral location of the rear axle,  the 105's use a pivoting T-Piece that hinges of the Diff and the two chassis rails.  To change this would be a huge job there is not much room for a watts linkage setup or pan-hard rod, especially with the exhaust pipe traveling over the axle.  Therefore the rear end of the car was pulled apart and new nylthane bushes where installed everywhere and yellow koni's fitted on all four wheels.  The back and was still not as tight as say an alfetta but there was a significant difference and all signs of axle tramping had disappeared.

With the back end under control it was time to pay some attention to the front suspension.  Before any mods where made the tie rod ball joints where replaced making the steering much more responsive.  To reduce the dipping under brakes some lowered and stiffened springs where installed in the front.  This made a big difference to the cars breaking ability making it much more predictable which really helped setting the car up for corners.

The car still suffered from bad body roll and if you even thought about breaking whilst turning you would be facing the wrong way before you knew what had happened.  This brings me on to probably the cheapest and most effective suspension mod.  Instead of buying a new aftermarket larger front ant roll bar four figure eight brakets where fabricated to attache a second standard anti roll bar to the  existing one (see photo)

Wow what a difference this made, the car actually had some under steer and it was possible to break into a corner.  The back would still come out under these conditions but it did it so much slower and more predictable that it could be used to balance the car into a corner.  This mod was done at the same time that the upper control arms where shortened by about 8mm giving around 3 degrees of negative camber on the front wheels giving a much more even tire wear pattern.  These two mods alone where responsible for a reduction of around 2 seconds at Winton race track.  At present the car is running  195 65 Yokohama 539's (the new replacment for th old 509's) on a 14 inch alloy rim