Having put a season and a half of racing on these components I am suitably impressed. The bottom arm design is superb and the finished article extremely well made. The bushes are the icing on the cake.

Accurate suspension set-up is time consuming at the best of times, requiring dogged patience. With the old style arms that required the car to be jacked up, bottom arm pin removed, rod-end turned, all re-assembled then set back on the floor again followed by copious bouncing up and down and rolling back and forth of the chassis to get it all settled before re-measuring – often ended up with folk sliding in to the 'oh that'll do' attitude as patience and time ran out. Made all the more tiresome by altering tie-rod length for caster angle alteration which in turn altered negative camber. And round and round you go trying to optimise the set-up. So being able to alter the camber/bottom arm length by simply undoing a lock nut, turning a tube nut, then nipping the lock-nut up again is an absolute joy, more than halving the time to do front end geometry set-up. Probably a lot less. And a whole lot less stressful too!

In my racing series we are not allowed spherical rod-ends in the suspension arms/components, so I am using the standard bush type trunnion version of the bottom arms (C-AJJ3360) along with the race spec hard metal-inserted bottom arm bushes (C-STR631). Performance has been excellent. Regular geometry and component checks showed no signs of wear in the bushes or change in the geometry settings.

The bushes have proven a real bonus as they massively reduce the side-loadings experienced by the standard-shaped/design versions. Adding caster forces the bottom arm to pull forwards, in turn distorting the bush away from it's natural shape. I have tried/tested all the different versions of the standard style bush, they all succumb to the pressures of this loading, eventually – sooner for some, later for others – to the strain. The distorted shape becomes permanent and the bottom arm is then 'baggy' on the pin. This, in turn, causes inconsistent handling as the bottom arm can move about. Not at all good. They also relieve 'stiction' in the suspension as they do not resists the rise/fall of the arm in use.

Part numbers:
C-AJJ3360 On-car adjustable bottom arms with trunnions for standard type bushes
C-AJJ3360A On-car adjustable bottom arms with spherical rod ends
C-STR631 Bottom arm bushes – angle-ended metal inserted
90IRHD hard rubber bushes – race use
C-STR632 Bottom arm bushes – angle-ended metal inserted rubber bushes – road use
2A4362 Bottom arm retaining pin, genuine
2A4362MS Bottom arm retaining pin, non-genuine 21A1882 Bottom arm bushes – original standard spec
21A1882MS Bottom arm bushes – top-hat, sleeved type fro increased stability and longevity