Thinking of taking my air box off and putting a cone filter on has anyone else done this and anyone any suggestions thanks

 

Sure, but you won't like it.

Take the unopened cone filter box, and install it in your trash can. ;-)

Seriously, your engine is much happier breathing properly filtered, cool air from outside the car, through a well-engineered system designed by very smart Swedes.

Or you can install the cone filter, and have your engine breathing much, much hotter, dirtier air from inside the engine compartment, through (usually) a filter of questionable design (in terms of how well it filters). Those things almost always reduce your gas mileage and horsepower, but boy racers might like them if you can hear the intake noise better (not an entirely bad motivation, granted).

Of course, the aftermarket filter maker will usually make some ridiculous claim about the filter increasing horsepower and mileage, but independent, unbiased testing shows it's almost always hype, and usually a lot worse than the stock air box.