http://www.ft86club.com/forums/showthread.php?t=81493
See the intake section. I've had multiple drop in filters and the GrimmSpeed intake. I would say that the GS intake had a very slight more "umph" to it than the drop ins, but it was negligible. Would recommend like many people on here to just do the drop in for performance, unless you're looking for something to bling up your engine bay.