For track use I need a bigger rear disc, and a better calliper set-up.
I've sourced a pair of ZR160 rear callipers that have a bigger pad area but bolt straight on to the existing 5EXi brackets. The handbrake mechanism also bolts straight back on.
I'll be testing this set-up at the Marlin open day in Wales 3rd June. With EBC Greenstuff pads should be an improvement. Note I've got a Wilwood pressure valve in-line to the rears ready for this set-up.
If you want bling then the best way to go is Wilwood Powerlites all round with the handbrake mechanism. Marlin can supply the lot. Jerry, on yours I'd get the 10.25" rear solid disc from Marlin at the same time. Job done.