Here is my answer to all of these bs questions. Don't you think the manufacturer has tried these products? Hell if any product could raise the gas mileage by 15% or increase hp by just putting a piece of plastic in your intake piping, the manufacturers would be all over it. they are always trying to meet new EPA regulations with gas mileage. So here is the easy way to find out if it is bs. Does any manufacturer put it on the car from the factory. if the product has been out for more then a year and it still isn't in any car from the factory, it is crap.