i had asked this before but still haven't gotten a straight answer. If one is going to do the gm stage kit (whenever it comes out) i'm thinking that we would be VERY limited on what supporting upgrades we can do without throwing CELS all over the place and/or voiding warranty.

Think about it this way.... the charge piping is about the only thing we could put on without voiding the warranty (considering we would do the CP previous to the GM tune) and that alone probably wouldn't add any additional power to GM tune since it's canned anyway.

or... how about a DP and CP, say with an intake and exhaust (the usual variety pack of mods) and assuming that these upgrades would be done previous to GM tune, BAM< Chevy puts the tune on and happens to see everything you did and as you go down to the dealer to pick up your newly tuned car, they also let you know that NOW your warranty has been voided, thus taking the SAFETY and WARRANTY factor away from doing the GM tune.

OR... lets say you did all those supporting mods AFTER tune, well as we previously discussed, its a canned tune, so don't expect that tune to allow room for more hp and tq, maybe a few here and there, but at what cost now that the tune is already been calibrated to your car, CEL's everywhere, screwed up a/f ratios and the like. just thinkin bout it all

basically, if you want to keep the advantage of the warranty from gm and still get some descent power, just do the CP before the GM tune and nothing else, they shouldn't give us a hard time for just the CP? and besides, is the extra 15 hp from a warranty killing DP gonna make a huge difference? or a total of 30 more hp if you did all the above, would that still make it worth it? does this make sense to anyone, it seems like it to me.

 

The GM tune will not tune down gains from additional mods.

Unlike flashing your ECM any other mod you do you can take off and GM would never be the wiser if you needed to do warranty work.

This isnt like all the other tunes out there were to gain any additional power from other mods you need a retune.

The GM upgrade only restricts power to protect the turbo from going overspeed.

This has been discussed at length, and both the Solstice and HHR have proven this is the case.

Not to mention two separate individuals from GM have been on both the HHR and Solstice forums and stated this as fact.

So, with the benefit of the GM upgrade, you will gain power from any other bolt ons you do. If you are that concerned about warranty you can take said parts off and GM will not be able to tell. Unlike if you do an aftermarket flash of your ECU.

 

I put all of my stuff on after the stage kit and there is a hell of a difference

 

no offense, but that wouldn't work, what are you gonna do, take off your DP and intake and put the stock ones back on just to go to the dealer then put them back on when your done??!! no way, too much work, way too much work just for a dealer visit??!! and again, since the GM TUNE is a CANNED TUNE WITH DEFINATE PARAMETERS AND A CEILING , you are not gonna make that make power whether you do the previously discussed mods BEFORE or AFTER the gm tune. you do the intake, dp, cp, and exhaust BEFORE A CUSTOM DYNO AND STREET TUNE.

Unless the instructions for the GM kit suggests certain supporting mods, it is meant to be done on it's own, simple as that. an example would be the cobb accessport for the STI (my former ride) cobb suggested no additional supporting mods for stage 1. for stage 2, you had to have atleast the dp, with full turbo back optimally. fools were putting on intakes after they loaded their ecu with the stage 2 program and were throwing cels and losing all their torque and screwing up their a/f ratios. i know the STI is different than the balt, but c'mon think about it.

if u want to discuss this, reply directly to what i have just said, my bottom line is CP before gm tune , then the tune and thats it.

 

If someone is getting the GM tune, it is generally to maintain warranty. So you will want to get stage 1 upgrade first, then do the bolt ons.

Tons of people switch out parts before going to the dealer.

 

i don't think your getting my point, first off, again that gm tune kit is a canned tune WITH PARAMETERS AND A CEILING, another words the fuel curves, boost and ignition are limited by those parameters, by doing the gm tune first THEN ADDING MODS AFTER IT, your asking your newly parameter set ecu to relearn to provide MORE BOOST, MORE ADVANCED TIMING AND MORE FUEL which all equals more hp and tq for our car. It (the ecu) will not relearn this due to more mods being put on after tune nor will ecu allow it because of the parameters set into ecu from gm tune kit. maybe, and i mean maybe you will get a few more hp but it will be at the cost of a confused ecu (which controls everything performance related or atleast monitors it very closely)

and i seriously doubt, no really doubt that people are going to jack up there car , wrench off a dp with o2 sensor connections , take off an intake with maf sensor and then put all the stock stuff back on then go to dealer, THEN get home and do it all over again, gimme break, are you hearing this? i may not know as much as some people on this site, but i think what i just said made total sense. gimme details, specific details if u want to debate this further, not generalalities.

 

Wether you do charge piping, or an intake, or exhaust, or whatever have you before or even after a stage kit it wont change anything with the computer wether its done before its reprogrammed or after. The end result will still be the same. It will have have its new fuel map, timing, boost or whathave you, and still see the bolt ons. Because even if you have had mods before a reflash when you reflash your still going back to square 1 and working up again. Just by adding bolt ons doesnt necessarily mean more hp and tq, it could just be mods that help the motor run more efficiently thus adding speed and power that way

 

Reading on the solstice form's , some one made about 15 whp with an exhaust . After so many key cycles he had it back on the dyno and it was back to stock power levels. Now the stock PCM isn't tuned for aftermarket exhaust yet he had a dyno proven gain the day he put it on .

GM has removed the learn down feature in the stage kit so the LNF isn't going to try and pull itself back to the stock power level. The PCM does have the ability to adjust itself to keep the command AFR , so if it's seeing more air moving threw the motor ,its going to adjust the fueling to keep it's AFR.

My opinion on changing parts before going to the dealer is ..... If you have a blown piston or have some other serious issue ......your going to change the parts back to stock lol .

Maybe your talking about going to the dealer for oil changes and other maintenance ? I'm guessing that most people with aftermarket stuff, that might cause issue's with warranty, only take their cars in when it's something major. I know thats how i am .

 

and the gm stage 1 for the LNF is coming with an intake fyi and you pay to play...if you want your comfy warranty you better know someone at the dealer or leave your **** stock. lol

 

Something I think he's forgetting too is not only the fact that these parts work on a stock tune and are "learned down", we're also only going to by limited be turbo overspeed now. If it works on stock tune, it will work on the stage kit too. The main difference is that the stage tune disables the learn down feature.

So what if it's a canned tune, these GM tunes are genius in the fact that they literally retune themselves based off of changing parameters (whether it be aftermarket part installation or otherwise). I doubt the stage kit will be any different. The tune is advertised to get the most power in a [GM] safe fashion.

If it was up to me, I would take it in for the kit, get it installed, then put the bolt-ons.. on lol... and then let the ECU figure it out like it already does. If you have issues, I'd try the key cycle method as well as the battery/ECU disconnect and reconnect method to start from scratch on its self-adaptation.

I know some of y'all have already covered this in this thread, but I wanted to put the pieces together to make it more clear.

Personally, my plan is to get the kit, add bolt-ons, and then maybe at a later date go for a separate tune (so I can use those new sensors/ECU software/higher boost abilities to their full advantage). I think the stage kit may be able to be used as a building block for an even greater tune later.

This is what a GM Engineer ("Flash's Owner") helping with the kit's development stated about it:

-----------------------

The stock production calibration is a sophisticated torque-based control system. It is constantly looking at all of the inputs - air temperature and pressure, charge air cooler efficiency, estimating density of intake air, and where the settings are for all the systems relative to a spark map to ensure the engine is protected for knock and detonation. It also estimates turbine speed with some very accurate modeling for given output to protect the turbo unit from overstress.

The goal of all of this control is to provide very consistent 260 ft lb/260 hp for all cars. If you make a change to the system such as improving the exhaust efficiency, then the control system will relearn with each key cycle that it is overproducing torque, and will "learn down" the torque back to stock level. If you do a back-to-back change that a dynomometer shows a gain of 15 ft-lbs, in a handful of key cylcles, long after you have left your dyno shop, the engine will learn back down to 260 ft-lbs. If you encounter a situation, such as a very hot day or you use 87 octane fuel, which requires an immediate spark retard to protect the motor, the good news is that the engine will "learn up" back to stock torque. But only back up to stock torque.

That is how the production system works.

In simple terms, the Performance Upgrade Kit turns off the learn down portion. You still have all of the protection features for the engine, such asg spark knock protection, turbine overspeed, or if you play with the wastegate link (which will, incidentally, probably set a boost fault).


So, essentially the PUpgrade you can think of as limited by turbine speed to protect the turbo from overstress and failure. At max turbine speed, whatever you can do to increase torque will be effective at producing more torque and power at a given RPM. This boils down to getting more molecules of air into and out of the engine. You can improve intake system efficiency by trying to make it less restrictive, including all of the flow path from fresh air intack to the turbo compressor intake, through the compressor outlet, through the charge air cooler (which also can be improved both through flow efficiency and cooling efficiency), into the intake manifold and through the cylinder head port and even intake valve openings. The easiest place to start is the air cleaner/intake pipes up to the turbo, BUT you must be careful when you start changing these things, as it is easy to create small areas of turbulence in the intake system which cause erratic readings on the MAP and MAF sensors and will set intake rationality codes.

The same thing applies to the exhaust side, from the exhaust valves. Legally, the catalytic converter must stay in place for the compliance to be legally valid. Improvements and lower restrictive exhaust in the cat-back section, such as what is available through GM Performance Parts should also be effective.

With the PUpgrade, these gains will not "learn out" like they do in the production calibration.

(Many thanks to the HPVO and Powertrain engineer brains for helping me understand and explain this info)

------------------
Located on page three of this site: http://www.solsticeforum.com/forum/f...-review-52407/

 

yeah, but nothing (power inducing mods) can get past the ecu settings to make it run more efficiently, that's my point, the ecu controls the floodgates for more SAFE AND IDENTIFIABLE power and if that same ecu is preprogrammed from gm kit those floodgates will only open so much to let more power out due to additional mods.

here's a perfect examlple, lets say the gm kit never exsisted and your starting with a bone stock ss/tc, you break it in, then proceed to put on a DP, CP, intake and exhaust with no preprogrammed tune or dyno street tune. more air is going to be sent to the motor for combustion with the fuel, (intake, cp) more fuel will have to be expeLled into chambers, (a/f ratio), then, that exhausted air is gonna leave quicker and with more urgency (dp and exhaust) meanwhile the stock ecu is going to have to learn these new changes and adjust and learn. will the car just naturally make more hp without the ecu's permission or so to speak?

Before that ecu can SAFELY allow these new parameters it has to understand these same parameters and make the proper changes throughout the car's ignition, boost and fuel and a/f ratio systems. THAT IS A HECK OF ALOT OF LEARNING FOR A STOCK ECU TO DO and do it in time before anything goes out of whack!! this is simple and logical stuff. thats why there are professional dyno/street tuners, these tuners do the learning for the poor clueless stock set ecu!

NOW, IF GM GAVE US A HAND HELD MODULE WHERE THE GM TUNE IS STORED ON IT, THEN WE COULD LOAD THE PROGRAM OURSELVES INTO ECU THROUGH OBD PORT. and then, only then could we do more mods after that because you could just go to a dyno tuner and have him put HIS CUSTOM TUNE piggybacking on top on the gm tune and the owner of car could switch maps and even switch back to stock if desired, just like how cobb does with their accessport.

i'm going to have to make a decision here myself, if i get the gm kit, i'm just going to have to be satisfied with maybe just some aftermarket CPing and thats it, in order to keep my warranty and not f$^! up my car. and if i want more power, i'll get the dp and exhaust but then I WOULD HAVE TO GO TO A DYNO STREET TUNER to make the proper adjustments, thus rendering my purchase of the gm stage kit useless (because the dyno street tuner would just go and change the gm tune kit parameters immediately and that info would be lost forever since i wouldn't have a module with the gm tune stored on it!! get it? AND, don't forget, that new tune from the dyno street tuner would be inaccessible to the driver too, (no dyno/street tuner is going to give you a portable module to hold their tune on it) do we finally understand or i am just completely nutz?

 

Look i don't want to kill any harts but for me and some of the other techs i work with at gm we don't think this things coming out GM main priority is fuel Ecomy not the stage kit they are changing the volt which was coming out with a 1.0L 3cylinder we just go news that Gm techs got the ok to change it to a ecotech 4 cylinder sooo yeah

 

and to this end, how would you really honestly know if it's something major, cars don't always let their owners know they are f@#$%&!! again, have you ever taken off a downpipe and intake and put the stock ones back on, then put the aftermarket stuff back on AGAIN, do you have any idea how much is involved with that??!! it's an insane amount of labor and you have to have the lift for that as well as the tools. I guess it would be worth it if you completely blew you engine, but remember, you probably blew that engine because you expected your balt's ecu to learn ON IT'S OWN all the crap you did to it.

 

You're right about the limitations of a canned tune... after all, it's canned, but that wouldn't be any different in this case than getting any tune with maybe a few mods and then adding more later. You're still going to have to go in again to "lock in" your changes so to speak if you're wanting to get the absolute most out of your specific combination of mods/engine quirks.

Yeah, a handheld would be great. It looks like GM's taking many measures at this point to make sure that doesn't happen (such as requiring a kit serial number as well as some other code that is achieved through using your specific VIN to allow for the download). That and Tech2s are hard to come by..

The tune is GM's property and it wouldn't be in their best interest to allow it to get out in a fashion that they may not be able to profit from it. On that note though, is there a way to "pull" the tune off of an ECU? I'm not familiar enough with the equipment to know. That would be great from a modding standpoint. You could tweak your tune while keeping the safeties in place. You just wouldn't be able to give it to somebody because of the VIN code security.

 

i have gone through a performance based school and i work for gm
so let me just set a few things straight

1 the stage kit does not come with an intake

2 the stage kit comes with a new map sensor (able to read higher boost more precisely) and a new tune which increase the boost to 20-22 psi and brings the afr closer to stociometric afr. if you own a tc you know they run rich, the tune leans out the afr.

3 the stage kit tune disables the relearn feature that is on the stock tc's so you WILL see the benefits of upgrades ( piping, exhaust, etc) however, the way the tune works is it is given a set afr, and every time you drive the vehicle the pcm see's what afr it is running and will tweak it slightly on the next drive cycle until it reaches that precalibrated afr.

4 you will ALWAYS see better performance with a custom tune. a custom tune will bring the afr right to stociometric. the gm tune was developed to be used across the country in various elevation and temp so they left a buffer zone so the cars would not be burning up motors.

5 it is at the dealerships discretion if they feel your aftermarket modification has caused the premature failure of a certain part. (if you put drop springs on your car it voids the warranty on the suspension ONLY, this due to added stress to the suspension) that said piping, intercooler, exhaust, etc is at the decision of the dealership doing the work.

gm tune will relearn after each modification, true you will not see as big of gain as you would with a custom tune but if i want to throw a intercooler and piping on my car i dont have to take it back to get it retuned all i have to do is drive it a couple of times and the car will retune itself.

hopefully this post will put some misconceptions to bed

 

Excellent information. Thanks!

 

1.)ok, i know the gm tune comes with an intake tube, not the typical intake we all think of, i knew that.
2.) the balt ss/tc runs rich stock? what? have you ever taken a whiff of the exhaust AFTER it has warmed up, not cold, because just about every car runs rich cold, that exhaust smells more like donuts than gas!! i start my bslt ss/tc in a very small enclosed garage and i can't smell a whiff of uncombusted gas! you sure about it runninbg rich stock? i had an sti that ran pig rich from my tuner and the whole garage would reak like gas after 2 minutes!! and just because it can read higher boost better, does that mean that the stock turbo and motor can take more boost from further mods?
3.)ok, the gm tune allows the ecu to learn a bit better, and maybe just a/f ratios? what about about the other stuff it will have to learn? and YOU STILL ARE TAKING A CHANCE WITH THE ECU RELEARNING ON IT OWN, you can't deny that.
4.) again, how wide is that buffer zone, we would need objective parameters, talk to any tuner about that., its important
5.) and everyone knows darn welll that a dealer can make any connection to other failed systems due to a mod, forget about that magnusson act that everyone quotes, you will have to take that to court and you will lose. these engineers are very smart and know the crap we do to our cars

so now people will just say, ok, if u get the gm tune and do more mods after that, well just go to a custom dyno tuner and get it re-tuned if u want to be %100 safe, well there goes ur investment in the gm tune, changed by dyno tuner and lost forever!! or just get the gm tune and mod after that and DON'T GO TO A DYNO TUNER TO RE-TUNE, drive around for awhile not knowing whats going on and hoping and wondering if your ecu is keeping up and learning and keep hoping and driving, then one day, you start knocking and hesitating like crazy on the top end, your boost creeping/spiking, running very lean , heat soaking.

ok, go in your garage, jack the car up with your custom garage lift, take everyhting off, put stock stuff back on, 14 hours later go to chevy and pray they don't know what's up!!?? so that's the choices?

 

1 stage kit is the same as the hhr map sensor and tune. tc's will see a little more horsepower gains just because they are manual

2 yes they run rich. you will not find a production turbo car that runs lean, that is the fastest way to destroy an engine.

3 the afr and boost are the main things changed by the tune. im not sure what other "stuff" your talking about but if you mean timing, well that is based off of the knock sensors so up until the engine knocks the pcm will continue to increase the timing. the pcm will relearn on its own but with the tune it will relearn to its set afr, unlike stock where it will relearn an limit the hp to 260. with the tune it will not reduce the power of the engine as long as it sees the correct afr.

4 i tune cars. and i have not had the luxury of seeing the specs on gm's tune so i could not tell you how wide of a buffer zone it has.

5 as for the warranty the dealership is given guidelines to base their claims on but when it comes right down to it they make the call. they do have the option of requesting a gm rep to come look at the vehicle but that usually takes about 2 weeks so most of the time they will dick you over to save time and money.

 

wow, still can't believe stock balt ss/tc run that rich, really man, take a whiff of exhaust after its warmed, u smell NO GAS, i mean maybe its borderline rich, i'm just used to rich meaning u can smell and literally see unused gas coming out of pipe.

can't you agree with me that it still risky blindly running mods after gm tune? i'm not a tech like u , but i have been around alot of tuners, garages, and people that have regretted exactly what i'm talking about, i'm not being pessimistic, just speaking from experience and using realism.

and besides, i don't really relish the idea of having 305 hp and 340 ft/lbs tq going to ONE FRONT WHEEL, let alone a wheel that steers the car. unless, ofcourse chevy comes out with a true full time posi front (lol) and sure, i guess 305 hp to one front wheel is great for 60-80 mph roll on races (and yes, i know there is tq management, but i don't want a CHEVYSPEED 3!) and people will say, hey i ran in the 12's with that 305whp, yea with slicks. i think that kind of whp is best reserved for awd sports cars and true posi rear cars.

i would be happy with just 270-275 whp to one front wheel, atleast i could still launch off somewhat and keep up with stock sti's n evo's

 

There is LSD also on many new TC's

 

Both of my tires spin when I'm on it so I don't know about this one tire thing. Do you have the LSD? The Cobalt SS got amazing reviews for the dampening of any torque steer, if that's an issue you're wondering about. There are LSJs that are making sub-10 passes with more "normal" ones doing mid 12's... so I don't think a mild setup like what we're looking at will be a biggie.

It's easy to tell if it's rich or not. Just check out the exhaust pipe. It'll be hard-core layered carbon black. Even more so than any non-DI or normal amount. That's easily observable and factual even if somebody doesn't know how to smell fuel correctly. I also see the gas coming out in the exhaust gasses from time to time. These tell me that it's rich, regardless of if somebody else told me one way or another.

 

they dont run pig rich, but they do run rich. also at an idle they dont run nearly as rich as wot.

the guys that designed the gm tune took into account the fact that people would be putting aftermarket parts on their car so they programed it to be able to account and adjust for those mods. besides none of the mods listed would even be able to change the parrameters enough that they would damge the engine. for a exhaust, intake, intercooler, downpipe, and piping your only looking at about a 50 hp gain max, which the pcm can easily account for them and adjust tha afr accordingly. the gm tune can adapt to those changes unlike a aftermarket tune.

also i have the lsd in my tc and i would strongly recomend getting one. it is worth every penny.

 

ok, i guess the lsd kicks in when launching the car, i have one too ofcourse. but i don't think the lsd up front can be considered along the same lines as a true posi, can it, what are the differences?

so if the gm kit tune is flexible, u tell me, should i do the dp and cp BEFORE or AFTER the gm tune, would it make a diifference, i really need to know this and the explanation that goes with it please

 

lsd=limited slip diff only works when cornering....our unit is full time posi until cornering.... when a wheel losses traction in a corner it locks giving you traction......a full time positraction unit does not slip=both wheels turn all the time....you could rebuild your unit and turn it into a full time-I used to work at randys ring and pinion

 

Ahh i installed all my own stuff so yes i know how much labor it takes. You don't need a lift , just some wrenches and a jack . If an hour of labor isn't worth it to you ....stay stock. Simple


Remind me again how simple bolt on's are going to blow up a motor because i "expected my car to learn ON IT'S OWN" ?