Yeah but add the K&N and now you really have a lean condition. Increased perf. does not necessarily mean decreased mpg. From the C90 test mule dyno map my hp has increased by 15>20%, torque has increased by the same or more and my mpg is slightly better than stock. I know for sure that the perf. is much better than stock. On our recent road trip to the Dragon I averaged 43 hwy, mostly doing 75>80. My best mileage was in the twisties, 48.5 mpg. These averages where calculated over close to 3000 miles in six days.
Bully Package
Cut wide open K&N
HK Sideburners
Pair valve removal kit
Blah, blah, blah....