I was involved in a board discussion last winter which I believe was comparing K11s to K12s. I mentioned the fuel mileage hit I took going from K11s (~45 mpg) to a K12RS (38 mpg). Someone else piped saying he had replaced his K12's ECU with an aftermarket unit, sourced I believe from Europe. He said it bumped his mileage back up to the mid 40s.
I'm trying to find that info again, as I'm interested in investigating that ECU further. In truth I'm not certain that the discussion was on these boards, but I've looked elsewhere, and searched here, and still can't find it.
Any help appreciated.