Got to have both if you're looking to improve performance. CAI gets air in. Headers and a good exhaust gets air out efficiently and a tuner makes it all work better....
It's hard to say exactly what the gains would be but there will be gains. The 5.7 exhaust manifolds are very restrictive and do not promote good flow. The coated headers will help keep the heat down under the hood.how much of an improvement would you say with the tuner cai and the headers? i been shopping around n the titanium ceramic JBAs are lookin pretty good n heard of gains up to 30 - 40 with all the mods mentioned but figured id ask the god of info haha