WTF with the 5 x 4 BC and getting axles?

They aren't exactly interchangable as far as bolt patterns go because the axle flange is farther out on factory big bolt axles and the drum centering register is bigger. Having both patterns then is a waste of $25. I'm only keeping small bolt on one car and that's the rare one (68 GTS convertible). There is no good reason to keep it on a modified car. Also, there's nothing wrong with factory small bolt axles if the horsepower AND traction are kept moderate.