My brother has a 2.2 SAI sedan LT (75k miles), and I have the coupe that is a non-SAI and is an LS model (33k miles). Both are automatic.

I drove my brother's sedan last night, and it feels totally different than my coupe.
Different because it seems a lot more responsive.
It takes off like a missle, and I had two adults and a baby in the car.
Seriously, I pondered if he had a 2.4 under the hood.

I feel like "I" have the sedan and he has the coupe, what the heck?

I get my oil done, the fuel filter and air filter done at the correct intervals.
Tires are filled to 32 PSI on all 4.
In fact I got my tranny fluid done at 33k miles (I know, unecessary)

I also had the injector service done at 15k miles.

So, I am really pondering if it is because he has an SAI or that my Cobalt LS coupe is just not broken in at 33k miles.

He has double the miles, but he gets his oil and service done randomly and goes over the change interval of oil commonly. Once he waited until 5000 miles to change the oil! I don;t know if he ever changed his air filter or fuel filter. He is bad with car maintainence.

Is the SAI actually a higher output motor than the non-SAI?
What other variables could there be?

 

No, the only real differance is that the SAI has an air pump between the intake and exhaust manifold.

He might have a differant program loaded on the computer, they put out updates every so often, and when I had mine updated, it felt significantly slower.

I also believe that there was a cam change for the 2007 MY. And now there is the LAP 2.2 with variable valve timing. Could be any number of things.

Maybe his car has a tune???

 

We both have 07s, and he has no tune.
In fact, he has zero interest in mods.

It might be the program version he has on his computer.

I know they did a reflash to raise the output of my power steering as it was causing problems.

I wish I had the same program, if that is the reason for the acceleration and response difference. It is pretty significant.

 

From what I have heard, our cars have a chip in the computer that goes out at 50k miles. Its reduces the power some until then because gm feels the engine is broken in better at 50k miles.

 

 

in his defense, ther were a lot of issues with LNFs not dynoing to their full potential when they were sub 5k miles...not 50k miles tho...lol

 

yes, this is true. they used sai as an emissions thing, and then in like 07+ or something they used a different cam w/ slightly retarded timing to achieve the same effect. this was told to me by a dealer when i went to get my sai removed, cuz i wanted to put on the LSJ header. they said they couldnt do it cuz it was illegal to alter emissions.

btw, i have a 07 sedan w/ sai, bone stock. all the coupes i have raced pull away very gradually pretty easy, so it could be that ur brothers motor is just a factory beast compared to urs, cuz every engine is different in some way.

 

And I would agree that the "full potential" would probably not be seen until around 5K miles. My car was particulary slow when brand new, and as the miles went by, the power did go up slightly.

5K is much differant than 50K. If he would have said 7K, I might have believed that was the cause, but not at 50K.

 

Dude it could be anything. The break in period could play something into it. Not all cars are drivin the same so things could seal differently. Could be as simple as gas. Do you get gas from the same place? Even if you use the same octane different gas stations have diferent amounts of dirt in the tanks.

 

I only use Shell gas.

I know my brother has randomly gone to 7-11, Circle K, Mobil and whatever else is convenient at the time to pull into. He does not care what gas goes in and he always lets the tank hit red before filling up. He even let it run out once.

Here he treats his car like crap, and it runs better than mine, unreal.

Both of us use 87.

 

^^ pretty much all gas from the major companies is the same..

 

yea, octane or gas station wont have much to do w/ it. especially w/ an untuned engine...

 

im not talking about octane ratings... figured you would understand that much
91 octane at shell is no better than 91 octane at 76 or chevron or most other places...

 

yea i kno, but im saying different octanes between 87-93 (standard pump ones) wont be a diff barely at all, unless u were to be tuned for say 91 or 93

 

o, ok. misunderstood what you were saying

 

Cobalt's have an oil life meter...oil changes aren't required every 3000 miles....

The air filter is also recommended to be changed at 50k....so I'm not sure what you mean by improper maintenance.

 

sedans only weigh like 200lbs more than a coupe

 

they actually only weigh about 30lbs more...

 

I got myself weighed at the track and it was 3025. A ss/sc guy weighed 3100. So yea, the difference is almost nothing like hunterkiller said