I just spoke with Vince of TriFecta, who does our tuning. He has some interesting and enlightening info to share. I asked him to please jump in here and offer his experience and opinion. He was working on a hamburger so give him a couple minutes.

 

https://www.cobaltss.net/forums/show...70#post2670670

 

hey i no longer have the p0420 code. can i go with the header w/ catless dp and completely remove the rear o2 sensor?

 

It will set other codes and you will get a light.

 

Thanks for providing the link and the sound files. So.... Is it safe to say your car is running correctly now? It sounds good and it sounds like everything is fine. Looks like the computer just needed some time to adjust.

 

p0036 and p0140

those clips where taking before the sputtering but it didnt happen since so im guessing the comp had to adjust hopefully that was it.

 

You can go with the "off-road" down-pipe without computer, but as Joe said, you will throw a code and get a light for the rear sensor... If you haven't already, consider performance tuning.


That is pretty much what Vince told me. I'm glad things have worked themselves out. At least they appear to have.

 

Dan, is your tunes a can tune but built for the specific mods I have? Or how's your tune work?

 

Vince is actually replying right now. I will let him answer your question.
Thanks.

 

i already have the trifecta tune with the p0420 code delete. will this make a difference?

 

Hi guys, Dan gave me a call and asked me to post about what we've learned tuning on the Cobalts with regard to exhaust modifications.

If you ask most mail order tuners whether the exhaust affects the tune, or not, most will say, "No, it the exhaust doesn't have an impact on the tune." That had been our experience as well tuning on the dyno - until the 2.2 Cobalt came along...

Traditionally, exhaust improvements only increase horsepower and torque, they don't affect the tune. This is not the case on the 2.2 Cobalt. We've been working with a customer that recently installed the Clear Image header on their car, upgrading from the stock exhaust manifold. The GT Tuner now supports data logging, so we've been having the customer data log his car all along, and we've been reviewing the log files to see how the car is running, both before and after the header installation.

With the stock manifold, we maxed out at about 24-25 degrees of timing at WOT before spark knock would set in. This is on 91 octane unleaded gasoline. After the header installation, the spark knock went away and last time I looked at a log file we were up to 27-28 degrees of timing at WOT. Fuel mixture was largely unchanged.

This departs conventional tuning experience - but it raises an interesting point - every engine is different and some can see an increased benefit from tuning with a header installation. Now, this customer hasn't been back to the dyno yet, but the general rule is the more timing you can get into the motor without spark knock, the more power it's going to make.

The data logs also showed an increase of 11% of airflow at 5500 RPM. We compared the airflow reported by the MAF before the header, and after the header, and this is how we came up with the 11% figure.

I've been told time and time again the stock 2.2 exhaust manifold is *very* restrictive so the increased exhaust flow with the header is likely lowering cylinder temperatures and pressures, allowing for the improved spark advance curve.

So, there's our experience for ya!

 

Okay... so that's saying that you guys send out a tune specific to vehicle mods right? Is there a link I can get to see prices and check it out.

 

Here ya go:

https://www.trifectaperformance.com/...r/default.aspx

 

Hey dan, that couldn't be right because I ordered a tri-y header w/ the ceramic coating too...& when I ordered the tri-y beth told me I was the only one to order the try-y at that point, but more importantly I ordered the tri-y W/ THE CERAMIC COATING. & my receipt says I was charged for it. So please clear this up for me.

 

I was told the same thing, although I went with the 2.5" downpipe w/cat so that may have been what she was referring to with me.

 

Anyone with a LSj and running a stock catback, how much of a difference in sound with the header/dp?

I get mine August 6th, but im too excited to wait

 

same here interested to know,

 

dan pm me when you get that shipping qoute (aprox.)

 

It is hardly noticeable. The idle burbles a little more. It screams a little louder under WOT. It def isnt a huge sound increase, which I think is spectacular bc I hate loud on a 4 banger...

 

I have the lsj and stock catback. No difference in sound guys lol. I was hoping for some difference but there wasn't any.

 

The header/dp won't increase the sound, it's the catback that does it.

 

im afraid mine is going to turn raspy if i get it without a cat

i have a custom 2.5 exhaust with a flor pro v force muffler

 

Very nice, lemme see what I can do and I might be in on the deal.

 

We have three TRI-Y orders. Two are getting ceramic coating. When I posted yesterday I didn't have your orders in front of me. I was half joking anyways. One is completely done. The other two are not assembled yet because we need to get final test fitting completed first. After we confirm the O2 bunf placement, the other two will be built, one raw will be shipped and the other two will be sent for ceramic coating. We have you all covered.

As far as sound, typically a header will not increase the volume of the exhaust, rather it will deepen the tone. The metal matrix hi-flow converters we use are very free flowing and don't do much to quiet the sound over a straight pipe. Like it was mentioned above, the exhaust/muffler is what determines sound.

Thanks.

 

big thanks to beth and dan over at clearimage.

living in canada makes it tough to order parts, beth was a huge help over the phone and dan gave me the information i needed to help me order the correct header/downpipe combo for my 2.4L

i am very impressed with their service, it was really top of the line.

thanks again dan and beth, i plan on getting my setup dyno'd so i will post once i get it in

again, big thanks, i recommened clearimage to anyone looking to purchase from them