This is very much like a K&N Filter Element, as JR were K&N's initial marketing people, and thus learned how to make their filters of them. I decided to go for the element, rather than the Cone Filter, because installing that with a good feed of cold air would require relocating the air-flow meter, and bolting the cone onto the end of that, behind the nearside front headlamps. It all seemed rather a lot of hard work to me, so decided that just having the barrel filter element was a far better idea.
This replaces the standard power valve that sits on the end of the injector rail, with a variable power vacuum valve. This forces more fuel into the rail the closer to the floor that your foot is, meaning that when you boot it, it moves!! Although the manufacturer refuses to give performance figures, it is reckoned to give about 10% increase in power output