I am planning on buying an air intake however I must decide on which one. I have a 2.4L Ecotec LE5. Naturally I should go with the K&N 69-4517ttk, it is designed for the 2.4L and claims to boost your horsepower by nearly 16 @ 5900 RPMs. K&N's website also offers a 2.2L version that only boasts a 6.6 HP increase at 4800 RPMs. That seems to be quite a difference. Another Air intake I haven't seen mentioned on the forums is the official General Motors part # 17800653, their website claims it is compatible with both 2.2L and 2.4L engines but doesn't make any horsepower claims. So, does the larger engine naturally work better with the Intake or is the intake itself produce extra horses? Lastly, does anyone have experience with the GM version? Out of Injen, K&N and GM which is best? Your help would be greatly appreciated.