Originally Posted by 540guy
so this increases performance and gas mileage both or did i misunderstand?
Also, i don't even have an m5 and i've never seen lower than 13.2L/100km. Somethings probably wrong there on my end.
Is that 13.2l/100km a combination of city and highyway? You should see around 10 or 11l / 100 km if it's highway only. My E34 M5 uses 9.5L/100 km on the highway at 130 km/hr. A retune by me will save you at least 5% on fuel costs.