Has anyone actually dyno'ed 2.5" vs 3.0"? I have a 3.0" diameter short ram from eBay on my LS and it performs just fine, but I'm curious as to how much different the 2.5" would perform. I'm fairly certain that 3.0" is better for me now, but I'm wondering if 2.5" would have performed better back before my other mods (especially last weekend's project).
Also, I noticed that the DIY CAI says to paint the inside of the pipe. Is that to make it flow better? The inside of mine is unpainted, but I'm wondering about the power difference of the inside being painted vs unpainted.