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<center><a NAME="On Rotor Warping"></a><b><font size=+2>On Rotor Warping</font></b></center>
"<u>Excessive heat, rapid cooling and numerous heat cycles </u>are what
causes warping" "The biggest problem isn't rapid brake heating, it's <u>rapid
cooling</u>. Such as high peak temperatures caused by a hard stop, followed
by a long cooling off period. This is why adding <u>cooling ducts </u>to
a vehicle with such an undersized brake system can make it an even more
efficient rotor-warping device."<b>&nbsp; Dino Cresentinin &amp; Steve
Ruiz of Autospecialty </b>(brakes)
<p>In practical passenger car terms, Cresentini and Ruiz noted that <u>warpage
is mainly a function of brake mass</u>. "The beefier the rotor, the more
peak heat it can absorb without problems." "<u>Cross-drilling</u> or slotting
the rotors helps, but only incrementally, and will not prevent the typical
problematic rotor from warping." "Turning a warped rotor will bring it
back to true, but this reduces its mass so it will <u>warp more quickly</u>
next time." "Vented rotors are good," Ruiz says, "but restricting (not
closing) the vent holes with extra material has proven a good trade. The
extra material makes the rotor more rigid as well as more massive."
<p>"There is no real substitute for proper <u>pad bedding</u>, especially
with carbon pads. Pad material transfer can be of a real concern when carbon
pads and iron rotors are paired. The trick with carbon pads is to bed the
brakes in properly, which transfers an even film of carbon onto the rotors
iron surface. If hard braking is tried too soon, carbon smudges form on
the rotor surface, forming spots of high friction, localized hot spots,
pulsing pedal,... and eventually leading to warped rotors."&nbsp;&nbsp;<b>
Hal Baer of Baer Racing Brakes</b>
<p>"<u>Braking sooner</u> is the best way to keep your rotors straight
and warp free." <b>Tom Wilson, Road &amp; Track</b>
<br>"Let your rotors <u>cool off</u> before parking. Driving hard, and
then parking the car and letting the rotors cool off while parked, causes
many warped rotors. Either drive around for a minute, drive less agressively,
buy bigger rotors, or use cryo-treated rotors to solve this type of warping
problem."&nbsp; <b>Larry Narcus, Carbotech</b>
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<a href="brakes9.html">Next</a>
<br><b><font size=+1><a href="brakes1.html">Better SHO Brakes Through Science</a></font></b>
<br><b><font size=+1><a href="brakes2.html">Expected Rotor Temperatures</a></font></b>
<br><b><font size=+1><a href="brakes3.html">Capabilities of Various Brake
Pads</a></font></b>
<br><b><font size=+1><a href="brakes4.html">Pad Part Numbers</a></font></b>
<br><b><font size=+1><a href="brakes5.html">DOT Pad Codes</a></font></b>
<br><b><font size=+1><a href="brakes6.html">Brake Survey Results</a></font></b>
<br><b><font size=+1><a href="brakes7.html">Upgrade Decisions - Rotors
vs Pads</a></font></b>
<br><b><font size=+1><a href="brakes8.html">On Rotor Warping</a></font></b>
<br><b><font size=+1><a href="brakes9.html">Other Brake Maintenance &amp;
Modification Tips</a></font></b>
<br><b><font size=+1><a href="brakes9.html#Links">Links</a></font></b></center>

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