My new GMS1 should be here on Tues, and will be installed on Wed (when the dealer does the PS recall fix).

This is the first performance mod I've done on this car...next up...K&N Intake..

 

you'll need a tune when you get the KN intake, your fuel trims will be way off.

 

Have fun with it, good noticeable difference from stock.

 

Congrats! BTW, the latest Injen CAI revision seems to have beaten MAF skew. Also someone mentioned the drop-in K&N filter skews some. However just enjoy the GMS1 by itself for a while, it's great!

 

Don't forget about the revised Treadstone CAI. I heard the Injen was revised before to fix the MAF trims.

 

That's interesting...I've been reading a lot about the K&N on threads in here, and haven't heard the "need" for a tune after the K&N (albeit understandable for maximizing performance gains)...how far off will they be?

 

If you decided on GMS1 for warranty reasons, then that's cool. But if max performance is what you looking for, you're going to be much better off using one of the other custom tuning options that are available.

 

Warranty is the main reason...only 8700 miles on the car and 2 years left...I am trying to maximize performance while minimizing risk of voiding it.

In two years, all bets are off :P

 

Hope you have better discipline than I did!

 

I was actually thinking about the K&N SRI (Typhoon), not the drop in...maybe my discipline is already at risk :P

 

https://www.cobaltss.net/forums/08-1...ng-car-225160/

 

Thanks...I hadn't seen that post. With that being said, where should I focus next (without a tune)? Exhaust-side I presume...I am not lowering (roads are way to bad up here in the great north east for that).

 

a downpipe will open things up a lot and you should notice a difference especially with gms1

 

Downpipe should be your next mod. A lot of people go catless, I went hi-flo catted from ZZP. Whichever you choose, a DP. After that, do the ZZP intake mod. Will cost you the price of a screw and that is it. Then, I'd say be happy with it.
If you do want more after that, most other mods won't add much power, especially with GMS1. They might add a little bit with a tune to really take advantage of them, but if you're worried about warranty then I'd say stop after the DP and the intake mod.

 

Can't go catless up here (NY requires a cat, so that limits me to a high-flow cat) on "newer" cars - one thing I love about building the classic/muscle cars - no emissions restrictions..

I'll start weeding through the DP threads and also look for the ZZP intake mod threads...

 

Hey if you realy want to go crazy. I taked to trifecta, he hold me someone did a trifecta tune ontop of the GMS1 (HHR SS). They were able to get 30hp more and 35tq more ontop of the GMS1. Something to think about. Only 350$ for 30hp. I dont know if there is anything else that can get you that much hp per dollar. And dude move down to FL or TX they dont check to see if you have a Cat.

 

I've been trying to get the wife to agree to a move back to FL for about 10 years now...don't think it's gonna happen (still trying though).

I don't want to tune until the warranty is close to up...only 8700 miles on it, so who knows what might fail and require warranty work.

 

GMS1 kit arrived today from CED (at below local dealer cost!)....

Appointment made for Thurs to install - based on the conversation with the service manager, this will be the first one they have ever done so I hope it goes well.

Now to get rid of this damn snow to really try it out!

 

I have my car in as well, going to drop by the afternoon and ask if its fixed. If not, I think ima get GMS1, my car has broken so many time now I cannot gamble with warrenty.

Price for me was $60/hr x 3 hours + $635 for kit (wholesale price).

So taxes and stuff, all said and done about $900?

Seems like a decent deal, trifecta would be around 500-600 and it voids my warrenty if something really ***** itself and my car is taken in for a full analisys.

I have a downpipe here too, so hopefully thats 10hp in addition to the GMS!, im perfectly fine with throwing codes during the summer, and plan to swap the stocker on for dealership visits and wintertime.

Not sure if the GMS1 and downpipe is a good idea.. ARGGHHH /threadjack

 

Not sure what they'll nail me on for labor, but they are pretty good here, so hopefully only a few hours (we'll see). They are doing the Power Steering recall at the same time (dropping the car in the am and picking it up that night). Cant wait!!!

 

Haha, brings back memories.

I was in your shoes too. I bought my 2009 with 1000 miles and I wanted to play it safe too. I didn't want GMS1 though because the sensor issues kept scaring me. People telling me they weren't made for our cars etc.

So I just didn't wanna risk the sensors failing on me.

So I decided on ZZP canned tune with spare PCM so I can switch for warranty work. Best choice I've made. Having a spare PCM has been very handy.

Now I don't worry about warranty and I can play with my car.

I eventually went Trifecta, but long story short. I learned my lesson, Trifecta is what I should have done to begin with. I could have flashed back to stock and no one would know any better.

I do wish I had sensors though, oh well....

 

Afaik the PCM swap is the only true way to go undetectable(im too lazy to do this). The reason I dont want trifecta is all tunes can been found, with enough mining of the PCM. And Id guess if your engine exploded and your asking for a new one, they try pretty hard to find out why.

 

This is why I have a spare PCM. I haven't touched my stock pcm.

 

I read that the BCM even logs ECM swaps (not sure how true) so...if they are really looking, the could probably spot that too. I'm not even close to an expert on that though so just to play safe, I'm skipping the tune for now.

GMS1 to start, then likely a K&N SRI or AED CAI...still trying to determine which one as it sounds like both should work on GMS1 with minimal fuel trim skew based on the latest readings. I think I'll stop there for now (other than some appearance mods/tweaks).

Probably also look for another set of wheels as I have two sets of tires (winter/summer) and hate paying $80/swap for them to prep the wheels, etc. Done it three times already - that could have paid for at least one wheel!

 

yeah downpipe, tune, and wheels are on my too do list, this summer I will pay for a swap.. from summer->winter-> back to summer... same boat as you.

I dunno, I went from a 2004 civic si with 105hp to my cobalt pushing 240-250? I think its fast as ****, so with GMS1 i think I will be content for at least another year.