I want to upgrade my intake on my '13 Mustang RTR, it's running a Ford Racing Tune (Part code M-9603-MGTB on Ford Racing's website.) and has a K&N drop in filter currently installed, and an Magnaflow axleback exhaust. I like the tune, it's nice and torquey, and Ford claims the tune will put you around 445 bhp/450 ft lbs of tq, but I want to increase what I'm making. So my question is, given that I now have a map of this tune already, can you build off of it if I get the Steeda high flow intake and increase my numbers? If so - would the tune cost the full 300 some odd dollars still, and, what other information would you need to get the tune as efficient as possible? (Tire size/Differential ratio etc). I've been a past customer of Steeda, the parts are awesome, hoping you can help me out. EDIT: http://www.fordracingparts.com/parts/part_details.asp?PartKeyField=12346 There's a link to the tune applied to my ECU.