Nope they don't do anything at all. Save your money.
Semper Fi SAINT. May you rest in peace.
he's right.
unless you're gonna go nitrous, that gives you something to drill rather than the throttle body directly.
but otherwise, it's not very good on our engine.
it makes a cool sound. thats about it

Im a Xbox 360 fanboy...and damn proud of it!!
They actually do work on caburated applications(just slightly better than a standard carb spacer), but don't do Diddly on MPFI/SFI motors. Not even enough to increase plenum volume any significant amount.
Ya, these things dont add much, or probably nothing, never seen any dyno proof, but also stay away from the tornado.