theres alot of talk about people changing it or using adjusting bushes when ypou lower your car! so what on earth does it do and what do you achieve from changing it?
cheers
http://en.wikipedia.org/wiki/Panhard_rod
the original length of the fixed rod was designed to work with the original size/dimension of the tyres, wheels, shocks to do 4 main things.
- at a static stable level unloaded ride height, it centers the axle to the chassis to ensure the alignment is straight and the tyres clear any part of the vehicle.
- only allow the axle to travel vertically and roll.
- during cornering, it transfers the lateral load between the axle and the chassis and keeps the axle relatively centered to the chassis.
- when the wheels/axle are at their highest travel up into the wheel arch under maximum load (big bump and/or hard landing and/or heavy loading etc), the rod is short enough to ensure the original spec tyres, wheels and shocks don't hit any static part of the vehicle.
by altering the whole suspension geometry with lower static ride heights, different shock geometry, different wheels and different tyres, the rear axle/tyres are more likely to be:
- off-center which affects alignment (crabbing/pulling/handling) and tyres may foul the arch
- hit the arch at the suspensions highest travel/loading
adjustable rods/bushes allow you to shorter the pivot ends of the rods to ensure the wheels are equal distance away from the reference edge of the chassis (arch lip) so the alignment is straight and the tyres won't foul the arch.