check out this page on CED's site showing dyno results: link

if you look at the part where it graphs the AFRs, it shows the run with the stock intake going excessively rich right where the power begins to drop. if you were to tune and get the correct AFRs, it wouldn't really be much of a difference in power, and seeing as the stock intake manifold makes a lot more torque in the 3500 to 4500 range (probably a wider range, since PE didn't kick in until 3500 in this case), the car would probably be faster with the stock intake if tuned properly.

 

So I would assume that although that might be bad for my 2.4 mani with tune is a big boost argument, still reenforces the fact that a tune can potentially really help this car. I am very interested in seeing some before and after dynos with tune and various mods.

 

i could see 160 - 170 at most.. but sorry us 2.4 guys are having enough time cracking the 190 mark with full bolt ons including a tb and a tune so if 2.4's are stuck in the 180 range .. no way a 2.2 is getting there

 

I was just wishful thinking I guess. Faw fewer balts will hit that mark with bolt ons and tune than I was thinking. Im reading the tune doesnt give as much power as i thought either.

Ok well then what do you think the 1/4 times for a 5spd and an auto balt would be at full bolt-ons/tune and shift plus for the auto?

 

Well currently I'm sitting at 140 whp (estimate only!) and I'm completely untuned.

With my mods I'm sure I could add another 10whp on top of that easily. Maybe more depending on how far I could advance the timing.

There is potential...it just costs a lot of money.

 

but you are an auto right?

 

I have heard from a few that a CAI, 2 1/4 inch full exhaust with cat and a 4-1 header have had dynoed 165hp with the 02-05 Sunfire and Cavalier.

This is at the crank, not the wheels.

The 05-08 Cobalt has 8 more hp stock, but I can't just add 8hp to those numbers.

I would guess it will give you around 170hp at the crank.

This is pretty good considering the 2.4 SS is close to that output.

Tuning for the Sunfire and Cavalier with an Ecotec lands at best 10hp, unless you go forced air induction.

The SS 2.4 is 7.3 second 0-60, but that is the coupe with a manual.
The sedan vs coupe seems to point at an average difference of .4 seconds slower on the 0-60 due to the obvious weight difference.

Your 0-60 should be around 7.7 seconds if you get the above bolt ons.
If you have an automatic, it is more like 8.1 seconds.
Tuning may knock off a tenth of a second.

Don't bash, I do not have test vehicles to perform a study of comparison, just the info off the net of which most stems from people here.

 

Very confusing to follow. I am in a similar situation. mike what are you saying to buy to see that increase in HP?

alex

 

I will boil it down to this, if you buy these items:
A cold air induction kit like an Injen, or AEM. ($200)
A 2 1/4" inch full exhaust including a 2 1/4" catalytic converter, and a 2 1/4" downpipe at a custom exhaust shop ($500) and a 4-1 header with Armor coat by Pacesetter as they are carb legal (look at Ebay), do not get the painted one ($220)

Go 2 1/4 unless you plan to get a turbo or SC.

Your Cobalt should at the crank be very close to 170hp, and torque will be close to 180lbs.
This would allow your 0-60 to be 7.7 seconds if you have a manual tranny. If you have an automatic, it will be around 8.1 seconds.

You will be close to what the SS 2.4 sedan is, but not quite.
The rest is more aggressive mods once the above are done.

You can get tuning that can raise your output another 10hp.

You can get the upgraded 2.4 intake manifold, they claim some higher max output but it seems to rob the mids.

You can get a larger port throttle body, which can add to overall power to a point.
If you go past the point porting wise the power band shifts upwards, in other words, you lose lows and mids to boost high end performance.

You can add a set of mild street cams for another 10hp.

Port the block on the intake and exhaust end.

You can add larger valves and stiffer springs to the head to raise your redline.

Higher compression pistons 10.5:1, or higher (requires higher octane).

In fact, you might be pushing it when you start modifying the intake end past getting an intake and ported TB with 87 octane. Just get 89 or 91 after said mods. Tuning is the best way to make all the mods run in synch with the computer.

If you do not want to ruin your warranty:
I would get the GM performance touring exhaust which will not have a larger cat included, and by law cats are not to be replaced until 75k miles unless damaged. Also, GM offers a ported exhaust manifold which wont ruin the warranty. GM also has a performance intake, but it is not as good.

Their exhaust is just as good as anyone elses, but their intake only gets 2hp as it is a short ram than gets hot engine air in even though there is a sheild to prevent it. Someone dodged this by adding a hood scoop and got a whole lot more hp from doing so.

This GM performance set-up is not as optimal but once the warrany is up you can add
the hood scoop, add the 2 1/4 high flow cat, and a 2 1/4 down pipe. If you want to upgrade to a header and ditch the ported GM performance exhaust manifold it is up to you.