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My 240 needs brakes, not just shoes, but new calipers. I've collected some info on the rear disk conversion, but not all. What I'm thinking is this: Toyota 4x4's up front on cross drilled rotors, rear calipers off a Maxima, again drilled rotors (Can I get these???) with stainless steel lines all around. Do I need a bigger master for all this? 280zx master maybe? And is a proportioning valve nessasary when both sides are upgraded? One more, e-brake, how is it set up?
Thanks, I know this has been beat around a little before, I just can't find everything I need on the limited time I have (work surfing!)
Anthony
 

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I can answer part of this for you. Cross drilled rotors = heat cracks. They are not meant for prolonged street use. Get Slotted rotors. Yes you will need a proportioning valve, as drum brakes use less hydralic pressure than disc brakes do. So without a valve the rears will be weak. I am not sure on the master cylinder, still researching into what is best there. I don't know if the factory e-brake cable will work or not I can't remeber how those calipers hooked to the cable on the 82 I stripped.

Hope this helps some
Matt
 

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Ditto what Matt said. You will need a master cylinder from a car that has disc brakes all the way around, the Z you steal the brakes from should work. The new proprtioning valve will be necessary to get the brake bias just right. Any E-brake cable is going to require some ingenuity. Hopefully you can cut your and put a new end on it to work.
greg
71 240z
 

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<b>RE: Disk brakes, ect....</b>

If cross drilled rotors cracked from heat, wouldn't they be even less usefull for track use??? On the street your brakes should never get the kind of punishment as on the track. Doesn't the 911 Turbo use drilled rotors? Not that what Matt said is false, it has just confused me a little.
Thanks
Anthony
 

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RE: Dimpled rotors

Has anyone ever seen any dimpled rotors for the Z? I've seen them in the Summit Racing catalogs for Mustangs and stuff. Like the name implies, they just drill a small dimple, like half way thru the rotor. Supposed to keep it from cracking, but still prevent fade. I imagine this wouldn't be any harder to do yourself than cross-drilling, just set the depth on a drill press to keep them the same. But I know opinions vary on wether you can do this yourself or not.
 

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RE: Disk brakes, etc....

ok, lets get it really confusing. Yes, the 911 had drilled rotors on their street car, but when they race it, I think they go to solid vented rotors. Thermal mass. Rotors that are drilled should be inspected on a regular basis for cracking at the holes. It all goes back to the original desige: if they are originally DESIGNED as a rotor to be cross-drilled and they're done properly they should work o.k. since the mass present in the rotor acts as a heat sink during the thermal cycling. Usually what happens, though is people punch holes through a solid rotor, don't deburr the holes, and cause stress risers. Since they have less mass now, they heat up and cool down QUICKER. Quick heating and cooling causes STRESS, stress causes cracks. Stock rotors were fine for John Morton running Riverside, much faster than we do on the street. A pad upgrade and larger friction material swept-area are areas to improve your brakes easily, and shouldn't cause the rotors to crack. Might grind them to nothing, but then, rotors ARE a replaceable item...
 
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