I replaced the gasket with just the basic circular one. I have a premium gasket just need to find longer studs to make it fit. And when i did replace the gasket it stopped back firing nearly as bad. Ill double check everything again tonight but im like 99% certain there isnt an air leak from where my exhaust bolts into the head. And if there was a pin hole leak in my exhaust would it still shoot flames out the end of my exhaust?