It's funny my wife is from West N Carolina, it's a totally different type of country slang in WV, Virgina, North Carolina and South Carolina. What is funny is they all think I have a country accent, because the old Florida accent is similar to a Texas draw and I think they all have one. The norther south is a totally different pronunciation and accent from the deep south. I can understand the Cajuns better than someone from WV or the western Carolina's. Then you get to Tennessee and it's like a blend of the deep south / Texas accent and the upper south.
The equivalent deep south colloquialism for that would be: faster than a raped ape. I don't exactly understand why apes are so fast when they are raped but apparently they are fast. The other one I hear, but not as much, is faster than a knife fight in a phone booth.
One of my other favorites that is tangentially related is:
Ya'll cover your ass faster than the new guy on D'block.
"Faster'n a pack o' dogs on a three-legged cat"