Generation IV Internal Engine - 58x 7000rpm+ misfire?

hey guys ive read somewhere that the 58x reluctor ring and sensor start to "blur" pulse signals at high rpms, is there any one that is having this problem? im hoping to use the reluctor and ckps on a 4cyl mazda turbo project using an lsj (sc cobalt ss)pcm. car will see 8000-8500 rpms.
thanks in advance