[Ant]

Scott,

Your setup and experience makes good sense to me, I have just been on the phone to Wilwood in CA, and they recommend the 120-6385-RS for my setup, Narrow SL6R with Thermotech pistons, these run a 16mm pad.

They are their narrow caliper but should be real good, so now the next stage is to make my hubs up, mount the rotors, and do a real world measurement, because I might just be able to squeeze the wider caliper in which runs the 20mm thick pads, and it may be borderline but I could run their nice 4 pot 1.88/1.75" differential piston caliper, but they are lug mount, and I think radial mount would be easier to fabricate for this setup, hence the SL6R.

Aussie Mike,

The AP's, Alcon, and Brembo prices for me are just way out of my logical thinking, and I cant justify the expense, (poor hard up old wage earner) the wilwoods are cheap, one downside is they have no dust seals on any of their performance calipers, but that would apply to the better brands also, the wilwoods are no heavier than these gold plated calipers, wilwood supply thermotech pistons at not much more expense. NZ V8 Supercar type series Holden/Falcon saloons are running the 120-5960-RS, SL6R calipers with alloy pistons, and some Dynalite 120-6985 calipers on the rear, and those guys are really doing it in 1450kg saloon cars, which surprises me a bit as the pad area in the SL4 and SL6R etc is the same and not overly large. I dont know the rotor size for them but would emagine either 13" or 14" which 1" obviously makes a big difference in leverage and heat transfer capability.