There's always a rather large debate about this issue of manifold vs. header. After 2000 models I haven't heard any issues with the OEM manifolds falling apart. Now the 91-99 4.0 headers are junk I will give you that. I currently have a busted manifold on my 99. But I am going with the stock replacement for 120 bucks. I haven't found much info that says the performance gains from a 120 dollar unit to a 350 dollar unit are worth the added cost.jeepmutt said:Buy headers. Stock exhaust manifold on the TJ, although similar in design to headers, is notorious for falling apart. Why do it to yourself again? I put plain black headers on ... Hedman maybe, Borla ... I can't remember. It's a PIA and took me 5 hours but it isn't difficult. I drive my Jeep, not show it, so I saved $ and went plain black. For the intake, I cut the tube from the air filter box, put a K&N on it, free breathing now.