i was just saying that there are other ways to do it rather than changing ecu. just because you don't fully understand them, doesn't mean they aren't as good. you even say on the other post that 'this is one of the best conversions you can do with your car"

to some people (e.g. Simon SECS and others) they're not that difficult to design and build. i could do it myself and sell them, but really can't be arsed. especially as there is already such a thing on the market that doesn't cost much so there's not enough profit in it for me to invest in the necessary equipment to make them professionally.

it's really not difficult, it's just logic and electronics. and it's not even expensive if you already have all of the gear to program microcontrollers. an external one is slightly more difficult than an internal to the ecu one, as the signals will need conditioning that's already done in the ecu.