Earlier today the NHRA Technical Department released additional 2013 Hot Rod Heritage Racing Series Rules Supplement Amendments These amendments document the rule changes that will come into effect beginning March 19, 2013. The 2013 Hot Rod Racing Series Rules Supplement Amendments can be accessed by navigating to the TECH, Rules, 2013 Hot Rod Heritage Racing Series Rules Supplement Amendments. The entire 2013 Hot Rod Heritage Racing Series Rules Supplement, with these amendments, included will be available online in March at NHRAracer.com and nhrahotrodheritage.com