schwinn Posted February 3, 2010 Share Posted February 3, 2010 Unlike you, some of us get our information from personal experience and seeing things with our very own eyes, not random text on some website. May I ask, then, what exactly did you "see" with your own eyes? Why is it that all the rest of us, who can drive equally hard on the same car and same stock rotors, when we use non-stock pads, we don't get any "warpage" later? In other words, why do people who swap to non-stock pads suddenly stop having "warped rotors"? Also, why is it that many AutoX and other racers use stock rotors and don't have warpage either? Link to comment Share on other sites More sharing options...
captainhook Posted February 3, 2010 Share Posted February 3, 2010 May I ask, then, what exactly did you "see" with your own eyes? Why is it that all the rest of us, who can drive equally hard on the same car and same stock rotors, when we use non-stock pads, we don't get any "warpage" later? In other words, why do people who swap to non-stock pads suddenly stop having "warped rotors"? Also, why is it that many AutoX and other racers use stock rotors and don't have warpage either? That's a good question, I switched to HPS pads when they were turned, so we'll see if there's any difference. I watched a set of calipers get run around the disc and it could not be more clear that the metal disc itself was uneven. It was also clear it wasn't "pad deposits." So read or think whatever you'd like, but I'm going to go with the physical evidence. Link to comment Share on other sites More sharing options...
rao Posted February 3, 2010 Share Posted February 3, 2010 That's wrong - there is no such thing as warped rotors - it is impossible. There is a website that proves this BTW, Powerstop rotors are made by TRW. This thread is completely useless Rob IF YOU CARE ABOUT YOUR CAR YOU SHOULD NEVER DRIVE IT Link to comment Share on other sites More sharing options...
Siper2 Posted February 3, 2010 Share Posted February 3, 2010 Save the $$$ and buy OEM blanks. There's no real advantage with DBA's. Check rao's recent thread for an even cheaper option that seems to have great results. I'm not sure what rao posted, but I just bought this set: http://www.cvrmotorsports.com/store/index.php?target=products&product_id=4934 $339 SHIPPED, front and rear, including Centric rotors and Hawk HPS pads. Add $40 for a black rust-resistant coating on the rotor hats (I did... I like how it looks, too). I was thinking about the DBA rotors, but honestly I don't need them. Not worth the extra $$$. CVR and Fred Beans both sell Centric rotors. Link to comment Share on other sites More sharing options...
schwinn Posted February 3, 2010 Share Posted February 3, 2010 That's a good question, I switched to HPS pads when they were turned, so we'll see if there's any difference. I watched a set of calipers get run around the disc and it could not be more clear that the metal disc itself was uneven. It was also clear it wasn't "pad deposits." So read or think whatever you'd like, but I'm going to go with the physical evidence. So, I assume you saw the rotor on the cutting lathe, and you could hear it cutting louder in some regions of the rotor, versus others. Right? Could it be that the cutter simply made less/different noises where there were pad deposits? What's more, who's to say that the rotor was perfectly flat on the lathe? If it's not, then it still sound like the rotor was warped. In fact, with that situation, it would cut a "warped" plane into it anyway... essentially MAKING a warped rotor. Unless you took a dial indicator on the rotor, and checked it with a known-flat rotor, I can't imagine you really know. Lastly, even if there is some surface wobble there, what's to say that's not normal? Stock calipers are floating-design, so they will follow the rotor along most minor deviations... that means you may not feel it anyway. As for saying it's not pad deposits... how can you be sure? In any case, you're running the perfect test now. You had your rotors cut, and are now running HPS pads. How long were the stockers on before you noticed "warping"? How long have you been running the HPS on the cut-stock rotors? On a related topic regarding cut rotors... check this out: http://oeqf.com/techinfo/index.htm Link to comment Share on other sites More sharing options...
KNS Brakes Posted February 3, 2010 Share Posted February 3, 2010 Some rotor 'specs' to fuel the fire. Rotor runout - or warping is generally spec'd at roughly 0.003" max or so. DTV - or disc thickness variation is spec'd to be less than 0.0005" or so - a level of magnitude less. So - the caliper can absorb some runout without shaking too much. The transfer layer however has to be uniform down to a very tighter tolerance. So - The rotor w/ high runout moves the entire caliper back and forth in it's slides and at some point creates vibration. The rotor with too much DTV is creating a small 'speedbump' which pushes the pads back in ever so slightly which creates pulsing in the brake pedal. Certainly you can simultaneously have both. An excessively warped rotor would MOST LIKELY only be caused by grossly overheating the rotor via a stuck caliper piston or similar. An uneven transfer layer is easily caused by sloppy OEM pads/heavy car/hard braking. It does not always need to be turned - Rebedding / sanding/ then as last resort turning. Trying to rebed soft OEM pads - not easy. They just get hot and crap all over the rotor again. dems da facts.... Link to comment Share on other sites More sharing options...
rao Posted February 3, 2010 Share Posted February 3, 2010 I don't understand this - rotors CANNOT warp, so why discuss how they could warp? Rob IF YOU CARE ABOUT YOUR CAR YOU SHOULD NEVER DRIVE IT Link to comment Share on other sites More sharing options...
ppettit2005 Posted February 4, 2010 Author Share Posted February 4, 2010 yep, hard braking... that's me! Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.