Originally posted by DemonSVT:
Intake resonator - yes (though I never had one - Isn't it Zetec only?)
plenum - umm... we don't have one and if we did it would be necessary to get the air to the engine.
air boxes - a proper one is great to stop heatsoak
mufflers - needed unless you are a ricer wann-a-be
1/3 for 4 
Intake resonators- Yes, zetecs and SE's have them. There are other kinds of contours besides SVTs Demon and since it wasn't stated- it could be applicable.
Plenum- Funny- I had to take mine off to put my CTA in and I certainly don't have an issue of getting air into my engine.
Mufflers- isn't a resonator a type of muffler? If so, we have a lot of "ricers" running this setup on their cars.
Airbox- great for controlling heatsoak and resiticting airflow.
