From what I've been reading and my knowledge of engines, after exhaust set ups, cai and eurocharged tunes (a standard modded xf Imo..which is the most modding I would do) I know your mpgs should increase..Im thinking since not everyone who's posted their milage is running a complete stock car these variables must decrease your fuel consumption somehow resulting in better mpgs

I'm finding it hard to believe these can get anywhere near 30mpg while doing 70mph on the highway and commuting in traffic
My brother traded his g35 coupe which had more gallons then the xf (although it was a 3.5 litre engine compared to these 3.2s) he struggled to get past 24combined miles
I'm just wondering how all you guys can get these high fuel numbers on a stock car that has estimated 25highway 17 city miles