Well I've decided to go with the Cold Air Inductions, Inc. intake found here
This one comes with a 9" K&N cone intake which I am choosing not to buy. Instead I will be replacing it with an Amsoil filter. I'm against K&N usage of oiled filters (lets not fight about it).
My question is, on the zzp site their Wizair comes with a 4" K&N as an option. Should I go with a 4" or 9" filter? Why?
Thanks.