Disk Brake Conversion Using the 1984 300ZX rotor and Toyota V6 4X4 Caliper
One problem High horsepower Z's really lack is braking ability. Stock Z cars suffer, but modified Zs really suffers from inadequate braking. One major problem is boiling fluid caused by the heat generated by the caliper and rotor. One major problem is the fact that the rotor on the 240-280Z is not very thick. Swapping to the Toyota 4X4 Caliper solves some of the clamping force issues, but the caliper never really was the problem when set up with the right pads. However, rotors did and still do suffer.
One way to get away from this problem is to buy a Wilwood racing brake upgrade, which will cost you about $800. A more cost effective way would be to purchase a set of 1984 300ZX vented rotors and a set of 1988 Toyota 4X4 V6 calipers. You will need to have a 1/2inch aluminum or steel spacer machined to fit between the Hub and Rotor. Usually you can find companies that make wheel spacers from T6061 aluminum for about $50 and those can be machined to fit for another $35-50. Companies can be found on the web or in the back of Grass roots Motorsports. Once you have all the parts you need only a few different thickness washers to use as shims to align the rotor within the gap of the caliper and you are set.
A few other tips that I use are the braided brake lines, a Wilwood Proportioning valve, 4 inch brake ducts running from the spoiler, a good Hi Temp rated fluid (Does not have to be Dot5), and good Performance friction or Ferodo pads.
Once you have installed everything and bled the brakes (Russel Speed Bleeds are another good addition) you should give the pads time to bed in. 300 to 500 miles of non aggressive driving should do it. Now you can go hammer. Next month I'll address the rear brakes.
Mike Kelly Kelly Racing Ltd.