According to the engineers at Omex a "sports" air filter by itself will make absolutely no difference. It will probably give you more induction noise that will make you think you are getting better performance. Getting cold air, instead of hot under-bonnet air, intake will make a slight difference. Note that the current Plus 4 GDI has a cold air intake the leads over the radiator.
If you want a real boost you need throttle bodies. It depends very much on your driving style. You may even loose a little torque at low revs but it will make a big difference if you are prepared to keep the revs up.
In the end, as the yanks say, you can't beat cubes: in other words a bigger engine. A saying not entirely true and particularly in these days of turbo charged engines, but it still has some validity.
Yes , agreed on this comment ! Plus you also need a suspension set up that will cope with the power and an LSD at the back axle and then when you've got all those you may well want ABS to stop ( that is after the bigger brakes ) and traction control !!! They don't do the last two on a Mog ? I am looking at all this and want the power and the rest and must balance all this out to realise the shortcomings of too much power !!
