7 1/4 rear strength

A 7-1/4 will last if you don't hot rod the car at all and don't happen to turn a corner where one wheel breaks traction and grabs again like on ice and snow. I've got a collection of seven of the things which have spider gears ripped out from either spinning one wheel due to a fast take off or turning a corner on ice with a basically stock 273. I even busted one with a 225 in a 63 Valiant. I have one 7-1/4 that has lasted quite well behind a 273 and now a 360.(driven mildly) It is a sure grip so I believe there is a huge difference between the open and sure grips 7-1/4s for durability. There were thousands of cars with 7-1/4 rears that never broke when driven like the family car they were but as soon as you get one wheel to spin the spider gears tend to rip right out!