[race24x]

I see a lot of back and forth. I was considering doing the Big Gulp, Kong X porting, 103TB and a 2.3 pulley. I have stock exhaust manifolds cats, but a free flowing muffler forget the brand but the mufflers are almost non existent LOL. Should I consider not doing the pulley? I see some didnt some did... Also I saw a post that included a Spark Plug change. Is this something that is helpful or better? How often should you change these plugs? Do you have to index them? Sorry went from a supercharged SS to the ZL1 and want to Mod some.