Yeah I would have to say mid 16's are not even close for a 2.3. I have the Zetec and ran 16.7 with shit tires and bad launch. Also only had intake. Now have udp, 65mm TB, intake, 2.25 cat back and my FocusFanatics sticker to add 15hp alone. Plus new tires Michellin hydroEdge they stick pretty good in the summer. Can wait to see what I run this summer. Oh yeah back to the 2.3 I say 15's easy.