Lance's comments are right on the money. I installed a set of EBC sport rotors on the front of my car at the end of January this year. By the end of April (approx. 3000 miles) my front rotors were starting to warp.
The warp was barely perceptible in low speed street driving (below 40 mph). It became much worse once the brakes were warmed up.
Loosening and re-torquing the lug nuts improved the situation a little bit. Eventually, I replaced the front brakes with SVT-size rotors. [I bought new caliper brackets from Bill Jenkins.]
The EBC rotors were good while they were new. If the grooves (slots) stopped short of the outer edge of the rotor they might not warp so easily.
Hope this little extra information helps.
Mike
1996 SE MTX, Desert Violet (Ford's name for this color blows chunks! I prefer Black Cherry
)
Dunlop Sport 5000s, Ray McNairy's THFix,
Magnecor wires
