its not the speed of the parts turning that will kill the rear end its the "shock" factor, if you take off at 6k and the rear tires just spin its not very hard on it cuz the parts are just turning, however if you take off from 6k with NO wheel spin at all and just GO the rear end will have a massive shock to it and will break lol, pretty much the stock 7.5 rear end on street tires will be fine, if you go to the track and drag it alot it will eventually break, but will last a while (if the install was good and the parts were new when you installed them)
with slicks... its not gonna last long
the spider gear will be what brakes.
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2003 REDFIRE COBRA #3938 of 5082 @ 05/27/2003 1 of 414
MGW Shifter, Stingers, JLT, SS Inserts, MM FLSFC & CC Plates, SS Lines, H&R Race springs, IRS Brace, MRT Hood Struts
ME.com Member #29 - 400rwhp/380rwtq