They may not interfere with shorty headers, but I doubt any small block with shorty headers is gonna make the really high HP/torque it would take to bust the bellhousing without them. Take a look at Myron's @Locomotion wheels up pic in reply #2. If he's never had a problem without them, either from too much power or the front end settling back to earth on those launches.....I wouldn't worry! @GTX JOHN may tell you the same thing as a long time racer. The only car I will ever put them back on is my 70 Challenger 340, which is a 100% numbers matching car with almost every single date coded part!