How well does it work with the monte carlo. and how much horsepower gain would you say you gain?

http://www.turbonator.com/index.html?id=overture

 

nope it is junk just like the tornado. our SFI v6's have tuned intakes. they are designed pretty well for the adverage mod'er. if you need to modify your intake, you will know. all these vortex things do is create an air restriction in our engines. i will admit that some older engines can see gains from them, but not ours. save your $$ and buy or build a cold air intake and exhaust