I recently picked up an SLP X-pipe with cats and the offroad add-ons so I can take them out. I also got the Steeda catback. I haven't put them on the car yet, but I'm looking to do that this weekend. I have been told that without the cats there would be not enough backpressure? I figured maybe I should upgrade the MAF and add a CAI with it. I was looking at the WMS systems and they sound good, but I'm not sure if I should go with the 87mm or 95mm. The car is bone stock right now except for the exhaust that I will be adding. I am planning on supercharging the car in the future. I don't want to push too many PSI since its my daily driver. Anyway, should I put the cats on now before I get the MAF and CAI, or does it not matter. Also, is the 95mm too big for the car now? I don't see it being a problem with the S/C when I get it.