I have raced and built winning Legend Cars for 12 years. If you spin the rotor and it is warped, have it turned. These rotors need to spin true, end of story. i have raced rotors cut to the min. for weight and I have raced brand new rotors thick as can be. It made no difference in the braking, guarantee it. I have races every caliper you can buy, brake man is the best, BUT THEY ARE VERY EXPENSIVE! i now rebuild calipers using my own rebuild kit that i have put together, they are half the price and just as good as brakeman calipers. I do not suggest the 21/4 caliper sold by US Legends, sorry i am a dealer, its not a good product! Run good fluid, good bearings, good calipers, and MAKE sure NONE of the brackets are tweaked. These master cylinders are notorious for hanging up, make sure your is not. i promise you I have spent thousands on brake pads, calipers, lightening, honing and on and on, its not necessary! e-mail me and I will be happy to share my experience with anyone FREE of charge!