I bought a v6 mustang as my first car and the car itself has been a nice little car. I put an ecu tune in it and a posi traction rear end and that made a ton of difference. I recently bought a 70mm throttle body and a cold air intake. the problem im having is that right when you start the car it idles really rough then smooths out after about a minute. the car also is sluggish off launch even when its being power braked up until 4k rpm then the car starts running better. ive put several tunes in the car and some work better than others and im running 89 octane fuel in the car. is there any advice that could help me figure this whole thing out especially the bad acceleration. it would be much appreciated.