yet, unless i'm totally out in left field, OE 45 year belts are ok to x.xx [?] et, and newer stuff to a lower et ? why aren't those mandatory to be changed out ? then, there are some tracks that allow aftermarket belts that are out of date to run to x.xx et, and some toss you out if you have aftermarket belts and only run 15.00 and slower. i know safety is a paramount concern, but if military aircraft can go way more years than a 10.00 car before a change out, and fast dirt cars the same, there is no reason for nhra to mandate a two year rule on belts except money being involved.