I am going to agree with everything Jim said. We have installed about 25 in the shop and have sold +/- 100 for others to install. We sold 3 last week!!!!! We get 10 drops out of a sheet of metal, we do 2 sheets at a time and that lasts about 2 months.
About 10 of my shop cars, including rentals, have floor drops. We have seen no damage to the drops plates from curbing. Even when Voytek hit the leading edge of the curbing at Indy and crushed the front subframe and steering rack, no damage to the floor drop.
By rule, the replacement metal is almost twice as thick. If properly designed and properly installed, it is stronger than oem. Just keep your bolts short.
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Over 200 race wins and counting.