Right here. http://www.cobaltperformanceparts.co...ion-p-215.html

2.85" with a custom tune. That's it.

 

This is the crap i'm talking about. Stop telling people this crap. You are wrong!

Please, show me proof that a 2.8 is OK with 42lb injectors. I showed you proof that it's not.

Now you are telling people to use a 2.7" pulley? WTF?

Did you see the IDC's of a 2.8 at 6,300rpm? Please stay out of this thread.

 

so it isnt safe to run a 2.8 with the gm stage 2 tune?

 

2.8 with 42.5 lb, tech 2 shows 90% IDC @6900
i live in texas and my car runs pig rich

 

a 2.7 on 42s daily?
wow.

 

He lives in FL where there is no cold weather to change his tune. Also IIRC his car is fucked up but he hasnt told us y yet....

 

now since its out of the question on getting a 2.8 on my stage 2 tune when i get it done does anyone make a 2.9" to fit the gm stage 2 hub or can i run a 2.85"? and i also live in NY where the weather always changes

 

No, Sir, you are wrong. Many people should be fine running 2.8 and 42.5# injectors. Not everyone in this country lives under 2500'. Anyone living near the rockies should be fine with 2.8 and 42# injectors. Now if you live at an elevation under 2500' I wouldn't chance it. But as for myself I'm in Albuquerque elevation 5600' and I'm running 2.7" and 42.5# injectors and the highest duty cycle I've ever seen is 84%. I'm also tuned at 12.1 AF. Put that in your pipe and smoke it.


Oh and the day I was reading 84% duty cycle the pressure was reading 3200'

 

Dude first off, stop acting like a child. Second, lets see some proof that your IDCs are 84% at 7,000rpm.

 

Greatt... Has anybody has problems w/ this yet though?

 

x2???

 

Hrm... the only people I see blowing their engines up are the ones with the "custom tunes", and there have been more than several. There are very many people such as I with the GM stage 2, 2.8 pulley, air intake and exhaust that are running fine. When I see this part of the "club" blowing up I'll start to worry a bit

 

Acting like a child, man you get on here and start telling everyone that something many of us have done is "dangerous". You have your "proof" and you ask for others to prove you wrong. Others have posted up that they haven't had any problems running what they are running and you aren't satisfied. You never brought up any of the key points that play in to just how much fuel you'd need. Like the fact that elevation plays a key role in what injectors you can use. I did just that and you still aren't happy. If I had a scanner I'd be more than happy to shut you up and show you my printout from tuning, Unfortunately I don't. If you knew anything about tuning these vehicals (or any others) you'd know that not only does elevation play a role in what you can get away with injector wise on these cars, but also temp, BP, humidity, let alone the type of injectors you use. GMPP injectors tend to be a bit rich, Lucas too. (i.e. the 42.5# run like 50's) But others can be a bit lean. Only way to true know is to have them flow tested right before you install.

 

as i said before IDC's don't = lean. That could but always don't. Thats why you need a wideband A/F read out along with it. If you have HPT and you tell the car to run rich the IDC's will be high but your A/F's may be safe.

 

i agree, everyone seems to think the gm tunes are crap.. but i have yet to hear of a car with a gm tune blowing up.

 

can you please point out where he was acting "like a child"?


The only "proof" you have shown is inconclusive....car specific....and as stated by a few people....doesnt necessarily prove that its impossible to get a 2.8 to tune safely.

and anyone who brings you an alternative suggestion you cut down and call a lier.

everyone is curious to find out the facts here, you really need to calm down and stop attacking members.
its not like if one guy says "RUN THE 2.7!!!" everyone will run out and do it....
and if they do....they are idiots anyway for not researching the mod first.

 

There are 4 RL's that live within 5 min of me and we all hang out all the time. 2 have a 2.8" with 42's and 2 have 2.7" with 42's. So theres your proof. Now out of those 4 cars 1 went full turbo, 1 got totalled, 1 went to 60's (me) cuz of a piston swap and a wanted higher RPM, and the other (with a 2.7") is running fine all day and the kid drives almost as much as I do. Proof right there. I, me, myself (any other synonyms of I that you want) ran a 2.7" with 42's WITH A WIDEBAND, on a GM tune and the car ran awesome and never went even close to lean. So theres MORE proof. To tell you the truth I really dont car what your IDC is cuz if your getting the fuel you need theres really no freaking difference.

That is true and the reason is because of this post by Rob from Intense:

https://www.cobaltss.net/forums/show...09&postcount=1

 

I am going to add to this.

I ran 2.8 on a Stage 2 for 12000km and never once had any problems. Not one. I won't say it CAN NOT happen, but it did not happen to me or to any of the other people I know IRL who did the same mod.

- SK

 

i would say mod at your own risk FTW!

 

i had 2.8 but when rob tuned me he said im at 115% IDC so i went back to stock stage2. i didnt have any problems but i dont wanna risk it. My .02 is, its your car have it as you will.

 

my friend just put a 2.8 on his car with stage 2, gonan try and get him on the dyno to see wats up since meister hasnt seen what a 2.8 does on the dyno, personally, the only people i see blowing up is on tunes with 2.5, 2.6 or 2.7 pullies, not bashing anyone, maybe thats not the case for everyone that has had engine failure but that seems to be the most popular trend. its just makes me think why gm choose a 2.9 for the upgraded pully that comes with stage 3 with the gm tunes that are available for that set up.
like i said, not bashing anyone or the tuning abilities anyone has, i was gonna go 2.7 myself but decided on the 2.85 because i was strongly advised that a 2.7 and lower is just too much boost, and after i see threads like headgasket issues and piston failure, im glad im running the set up i am.

 

Acting like a child.....here. Completely uncalled for.

Listen to you man. That's your proof that a 2.8 is OK? That's some hardcore proof.

 

you need to sit down and breathe. youve given your piece....people are paying attention....now stop jumping down everyones throat that has a different opinion or suggestion on the matter. you are NOT 100% right. you have proof that in ONE circumstance the 2.8 was to much. we see that.....if you keep ripping on people every time they bring up ANY kind of information contrary to your beliefs you get pissed.

just relax a little and dont assume your right when obviously there are situations when your theory is wrong.

 

I'll say it again no one here is completely wrong BUT If you tell the car you want this much fuel at this rpm or a commanded A/f of 11's or somthing like that its gonna try and do that and the IDC is showing what duty the injector would have to be at to fufill that request. That doesn't mean that your running lean It could be a sign but it depeneds on how you set your tune up. you need the IDC reading along with a wideband A/F read out to figure out whats really going on.

 

CTCOBALTSSS.....This thread is all bullshit. Like many have said there are many different factors that go in to your IDC being too high. You keep showing eveyone YOUR 1 example and telling them to prove you wrong. when they show you how it is wrong you shoot them down and call them children.

I am Stage 2, 2.9. And my IDC have not come close to the "danger" zone. within the week I will be installing my 2.7. I have no fear that I can safely run a 2.7 on my car with the 42's. I will drive safe until I check my IDC and A/F in al rpms. Then if MY CAR specifically (Since everyones will be different) doesn't like the 42 2.7 combo then i will upgrade the injectors.

But how do you come off and just say... IT WONT WORK. when it all depends.