What to do to change the ecu?

[k_riyat]

hi,
im thinkin of changin the ecu in my 325i, right now it has a ecu which ends in 164, but i hear the 173 are the best. so is it worth changing to a 173 and if i do what do i need to do is it jus unplug the old one a plug in the new one and your set?
or should i jus get the 163 chipped?
thanks for the help guys

[2_stroke]

ecu is plug in and go i think bro

[k_riyat]

i jus ordered a chip from evo. n they wanna know what ecu i got should i change my ecu to 173 n quote that to them or jus stick with the 164?

[2_stroke]

i dont know about the numbers on the ecu's personaly for the money its gonna cost for another i would just stick with the one i had, unless its ballsed up in some way lol

[zimmer-320i]

not to sound dumb here but what diffrence does the ecu make by using a 173 ecu over a 164 or a chipped 163?? and what ecu would be good to use on a 2.0 as supposed to the 2.5???