There is no 08 model in the US. Ours starts with 09. The engines, turbos, and for the most part, trans are all the same. The newer ones just use more of the reserve capacity that the older ones left on the table for aftermarket tuners. Word on the street is that the 2014 does actually have larger turbos. We shall see.
'15 AW/SO F80 M3 6MT: IND cosmetic package, Gloss black grill surrounds, Macht schnell 15mm spacers all around, 3M crystalline
'07 997 TT 6MT, Arctic Silver/Sea Blue: FBO, stock turbos, Cobb/PTF custom 93/E85, H&R, 19" BBS CH-R in widebody fitment. 6.700 60-130, 93 octane