Installing the gmpp cat back and k&n filter element, the 2.2 is more snappy off the line and pulls real nice to 6500 rpm, but the best part is the 6.6Lper /100km that I like.

 

I have the 2.2, only because the dealer had mostly 2.2s on the lot at the time. The 2.4 they did have was a white 2LT, and I dont like owning white cars with all this nice red Geargia Clay we have around here. I really wanted the Cyber Gray Metallic color, but they only had it in the LS very base model, the only true option installed from the factory or dealer was the automatic transmission. I love the car, like the get up and go, and love the fuel economy. I didnt realize that the 2.4s required the higher octane fuel, so i am very happy that I have the 2.2 now. 8-D Hope my 2 cents helps in your descision.

 

I wanted the cheapest car my dealer had with an automatic transmission. My car was almost a year old and still on the lot, it had missed two price increases, and that made it cheaper than the other LS models. I find the 2.2 has plenty of power, and the regular gas is a huge plus.

 

My son got the 2.2 in his '09 Cobalt mainly due to the gas mileage (he has the 5-speed also). He just installed a GMPP cold air intake. My HHR doesn't count. I have the 2.0.

 

I've got a 07 LT with the 2.2. Aerage 36mpg. Only real compliant is that is wont kick down a gear if I find myself going toooooo slow up a hill. Hit the hill at speed and everything is OK. But let it slow down and it wont boot back up to speed.