If I have a s/c with a TRD exhaust(soon to be magnaflow) and there is a possibility that I am running a bit lean, what would doing the deckplate mod do to my performance? Would it be better to not do it?- thanks

 

Unless you plan to add fuel mods to the list, then leave the airbox stock to reduce the chance of leaning out. The fuel mods are going to run you about $1000 and you an piece them together.

......or get them off gadget's site in a kit:
http://www.urdusa.com/Merchant2/merc...Store_Code=URD

check this out:
http://www.gadgetonline.com/fuel.htm