What sort of difference does it make?
I.E. Fuel consumption, Power ect.
Not sure what it contributes, but had it fitted by Allisport when they fitted the large intercooler, adjusted the turbo and increased fuel.
With all the additional mods, BB now weighs in at just under three ton and still pulls 80.
Regarding mpg, thats a pile of pooh (20 mpg), but then again, nearly three ton......
Chris