What will i need in my car to see biggest gains.
(Kingston upon thames, UK)
i drive a 2007 BMW 520D E61 touring LCI.
Since owning the car its been modified quite a lot. i have done EGR delete, DPF delete, changed my turbo from Mitsubishi to garret and done bigger internals also, I've also had it mapped.
I've been driving like this for about a year and a half and as i use my car daily i get 28-31mpg around town and 42-48mpg motorway (i have a bit of a heavy foot personally lol)
What would i need to do if i was to buy a kit to get the maximum gains?