thank you. at least the moderators on this site know what im talking about

 

Edit: I suppose the way it would barely run and the smell right after it happened that's it's possible that the engine is still intact and one or all of the injectors were stuck open. I'm sure they'll do a fuel pressure test and a compression test first.

Are you saying before the engine blew or while the engine blew? Because before hand, I thought about it being a leaky injector or something but I retained 26 mpg all city and the exhaust didn't smell like it was running rich.

As you can tell, I didn't actually try to fix the car nor to diagnose it. I was just trying to act like a normal customer and let them fix the car and put the warranty to use. I noticed all of the signs, but I didn't actually diagnose it down to the problem. If they give me a new engine then that was a smart move on my part, hopefully they don't try to dick me around because I have alot of ammo in this instance.

You must have misread my post. I am just stage II with NO aftermarket parts. I am not talking about the IDC, however it is HIGHLY likely my injectors went static.

I'm actually playing dumb with Chevy (Something that I hate doing) as this is my first new car and I just wanted to have something that I didn't have to hassle with. I am not horribly mad about what happened just yet because as long as they fix it then I have a new engine that I can break in right this time.

This time around I'm not going to allow anything to slip past me.

 

Oh i'm going to monitor it very closely. I just have never had a brand new car that I didn't fix myself and I thought I would give it a shot; bad idea. If you have the knowledge to fix it yourself that is ALWAYS the best way to go.

 

Haha, yeah I think that's how curse words were invented was through working on cars .

 

Our cars are weird, got a friend(Saturn Tech) 05 redline with stage 2 and 2.8 pulley tapped into it with hp tuner and his injectors are a like 92% or something, everything else checked out just fine,and yet it runs like a champ, better gas mileage then stage 2 and of course the power. he beats on it everyday and im just waiting to see what happens...

 

I know its risky.
I know the canned tunes arent great.
but you and I both know that the heat created from overspinning the blower has/will pop an engine before the 2.8 will.
if your above 2000ft alt....2.8 actually starts getting into the safe range again.
and also...the "dangerous" point of the 2.8 is only when >6500rpms....


but I completely agree that tuning is important. and cooling even more so.
especially when going <2.7

 

Just so you guys know my old setup was with 2.8 and stage 2 when I got my aeroforce guages I immediately called a local tuner because the engine was pulling about 4 degrees of timing. Well I now run a 2.7 and 60's run a solid 11.7 afr across the board and have 0 knock. I do get a hiccup every once in a while but you cannot win them all.

 

Wow what a shitstorm of opinions, facts, and speculation.

As I see it, the facts are.
-Anything less than 2.7 overspins our Eaton, high IATs are the devil. We all wouldn't be ripping our babies apart for cooling mods if that wasn't the case.

-Who here has verified that the IDC formulas are proper? The only time someone ever read the Tech2 data and converted with GM's formulas, Stg 2 never went above 74% IDC. I have seen many HPT logs showing IDC's on stock cars and GM staged cars in the 100-120% range. General Motors DID NOT release a car stock that would push the injectors to that range, period. How many stock LSJ motors has anyone ever seen blow for this reason??? Maybe we should have an educated thread going over the pulse width formulas and conversions, this debate needs to die one way or another, lol.

-This is not to say that 60 lb injectors aren't a safety net, but they are overkill IMHO. I've seen 2.5" pulley cars on 60lb tunes that never even get to 60% IDC. In a returnless system, that is not a good thing for our stock pumps.

-I have a scan gauge and monitor knock. I got more KR on GM's first try at the Stg 2 Tune, with the Stg 2 pulley than I have ever seen on the 2.8

-I have over a year on this very set-up and shitloads of track runs and "spirited" driving. I had more problems with my car stock and with Stg 2 alone, then I have ever had since.

That being said, Tuning is never a bad idea, and our cars certainly need it. But as long as you monitor your A/F and your KR, the 2.8" is about the best matched pulley for our engines.

 

Man this really got me thinking. I was reading that the Stage 3 pulley is actually 2.99 or a 3.0 pulley that I had with the stage 1 flash . I bought the ZZP 2.9 thinking it was the same size as Stage 3's pulley and I have the mods for the stage 3 should I be worried with the 2.9 ZZP because it is not a 2.99 . I do have the coolant mod so I should be ok right?

 

You are fine man, but a tune is never a bad idea. Whenever I have the spare funds I will be picking up HPT

 

ok cool , Can't tune the Stage 3 PCM it's locked. But maybe the stage 2 PCM I will get tuned . I know a shop near my work that might be able to do it.

 

^Where in MI are you from?

 

Whoa buddy, never questioned your education man. Alot of us are educated.

The only question I asked was how certain anyone was that the IDC calculations were correct

Alot of us have been wrenching on cars for a long time and know how to monitor and check symptoms. I have seen many more LSJ's destroyed on 60lb injectors than anything else.

 

Troy MI

 

I don't think it has anything to do with the injectors since they just supply fuel when they are told. It lies more with the pulley size and the tune on the vehicle.

 

Right, my point exactly, nobody running 60lb injectors is on a GM tune.

I have yet to see a stock LSJ blow for this reason, and allegedly they run with ungodly high IDCs as well.

Cool cool, have you been to the track yet?

 

Alrite i'm going to skip reading thro the 3pags of farily useless and uneducated BS

I have seen a few educated people posting in this thread so far so i can assume some light has been shed on the current subject.

to the OP get HPT as your next mod, it will benefit you and others around you more then you many understand.

here goes....as a disclaimer i will say this first, I am an experienced tuner, a vary educated car guy, and i don't talk out my ass on subjects like this.

a GM set of 42.5lb injectors combined with a GM stage tune will lead to scary things, not a guarantied blown engine but other scary things such as...

static injectors
uncontrolled AFRs
increased cylinder temps
fouled spark plugs
just to name a few.......

any time your IDCs get into the 90% range the injector is on the border line of its pulse width response and fuel control accuracy.

now to be blunt.....

people who say running this set up is "totally safe" are full of ****!

now altitude, air density, commanded AFR, ect all play a role in your IDC because injector load is based of those parameters.

you can run a set up with CRAZY high IDC with little to no issue, however its VARY uncommon. and once people who run set ups like this get an HPT scan they often change things around to lower problum areas like your IDC.

any IDC OVER 100% is BAD.... END OF DISCUSSION!

you take an injector static enough times and it WILL fail....thats just how it is folks.

if any one has any questions, or whats to argue any of my points please go for it as more information can be shed on this subject.

 

bow down.
everyone else is useless and uneducated.

 

Hearsay, bring proof not what you heard.

And the chart would not be lying... for that particular Cobalt. Have you ever noticed that every Cobalt may have, to some degree, many of the same mods, yet they all produce different amounts HP and Torque? Yeah, exactly, no two cars are really alike, what might not work for one, may work for another and vice versa.

I've had my 2.8 Pulley on for a few months, no problems. When I first put it on I dynoed the car with the Stage 2 pulley and with the 2.8 pulley, the guy at the shop, who's been tuning cars for many years monitored the A/F ratios on my car (That's my Cobalt) there was no differences between the two pulley's (Aside from a little more boost). That does not mean the injectors were not working hard, they could have been, but the car never ran lean, period!

Now, everyone is assuming certain death!!!

Stage 2 + 2.8 =

Not, think about it, what are the ingredients here, Stage 2 + 2.8 = more air, possibly running lean = Death, but wait a minute, I would have to be driving my car hard as a motha' F'r to kill my car, constantly going wot no matter where I go to achieve lean death.

I don't live on a race track, hello.... My car barely sees boost on most day's, and because of that my engines not even spending any hp on running the blower, why because it's mostly running in vacuum. That being the case, I don't think I will have a dead car anytime soon, as a matter of fact; I am averaging 26MPG City.

Now, just so you understand me, I am not arguing, fighting, or bitching. I truly appreciate the concern, but do not pass me off for being un-educated about the Cobalt. Second, thank you for the comments, and in the end, I think I will go with HPTuners, because I would like to see how hard the injectors are working, even though, I think (I read it on this site) that HPTuners is not quite accurate with our cars and the IDC's.

 

I think your talking about me......

soooooooo.....


nonononn i never said that nor meant to imply that, i just grow tired of kids posting information that they read on the internet or that there SRT buddy told them is true.

I in no way, shape, or form meant to imply that i'm better then any one, I just wanted to state that i am educated on this topic.

 

Thank you Denny, this is the type of response I was looking for, HPTuners, will be ordering it soon.

 

hope everything goes well. HPT is what ive said from the start. tell us when u get it. im done with this thread. peace

 

all of itttt!!

 

Just out of curiousity... what kind of power are these people with these supposedly "maxed out" injectors making?

 

You won't get 42.5 static unless you decide you want to run a 11:1 AFR which in my opinion is too low. My 42.5 never go static they get to the low 90%, never 100+ according to HPtuners.

Also the stock injectors that GM sells in the car go over 90% IDC all the time according to HPtuners. GM spends YEARS testing their powertrains before you even get to buy. The test the stage 2 at the track for several seasons. So according to your argument every LSJ ever sold by GM is a ticking time bomb for failure because they setup the injectors to go 90-100% at WOT.

The only cars I have seen with a failed engine are the one running with 60# so they can keep the IDC's below 80%. Your argument may look good on a webpage but it isn't looking good in real life. How do you explain this?

I am shooting a 75 shot and gaining 105whp over my baseline with the stock fuel system and 42.5 and dual pass intercooler for over a year. I am still fine and hopefully I will continue that way. I have ideas why I think I haven't had engine failure yet, we want to discuss that. Yet all the 2.5 and 60# injector cars that are hitting 70whp over their baseline are melting pistons with meth injection ect.