[muzzza]

Sambo, Your question re roll centre goes something like this.

I mentioned the Holden sub frame is lower in a Harrison than a standard Commodore ( measure for yourself ) ..........this is equivalent to lowering a Commodore without addressing all the other suspension parameters.
Simply talk to anyone who has significantly lowered a Commodore or Skyline without addressing the other issues.......No1 problem ....Bump Steer !!
That is why the market is full of correction kits.
Raising the front roll-centre back to its correct height will increase front roll resistance, reduce suspension compression of the outside front wheel during cornering (less roll). Weight distribution is improved and camber angles don't change as much.......result better corner grip, usually less understeer and improved cornering stability.
Raising front roll centre would also improve the roll axis to make it more compatible with rear roll centre. ( will reduce pitching )
There are a stack of other complex issues involved as well.
The Cobra being a least 10% shorter wheel base than a Commodore, means we have Ackerman issues. Reduced Ackerman is fine when rear tyres are sliding across the race track ( front wheels will remain straighter - ask the drift guys ) but at lower speeds you would get better corner turn in with a little more Ackerman ( Outboard steering arms moved in )
Best solution is always a suspension setup, designed and engineered for the car where adjustments can be readily done........just ask Craig???