What are the typicaly changes expected from installing the GM Performance Stage 1 to the HHR SS. Im aware the HP increases to about 290 and torgue expected increase is up to 340.

However how do those numbers relate to the stuff we really are interested in..... Like 0-60 and the qtr mile times and trap speed.

Im also interested in how much the stage 1 affects MPG. I get pretty decent numbers were my 260hp HHR SS at around 26 MPG mixed driving.

 

1st off. My pet peeve on this. It is not called a Stage 1.That is a made up internet name. Correct name is GM Turbo Upgrade kit,or,GMTU kit.Yeah, the Stage 1 name sounds cool but is incorrect.
(sorry.this is not directed at you personnaly RBodeman,just those that use the wrong description of the GMTU)
2nd. The numbers are 290hp and 315tq in the HHR SS. Not 340tq.
3rd. Lots of numbers out there on the performance gain. Not sure exactly which are spot on accurate.
4th. Again lots of opinions on MPG's but most seem to notice a small increase as long as you can keep your foot out of it. My first road trip of 200 miles showed an increase of about 1.5 mpg.

 

This upgrade kit is pretty much obsolete now.

HPTuners has 'unlocked' enough of the 'code', so you don't
even have to go thru the expense, & sometimes, the grief,
that this kit has.

You don't need anyone ripping into your wiring harness, to put in
special sensors, like the GM kit requires.

There are alot of good 'tuners', over on the CobaltSS.net forum.

Don't get me wrong, this kit was great, when it 1st came out, as we didn't
have any other options at the time. It was, & still is, a way overpriced,
option.
A good 'tune' will give you more power, & better mileage, at half the price of the GM kit.

The HHR SS is a Hot Rodders dream.

Very little is needed to go fast.
A good 'tune' alone, will get you most of the way there.
Just add a K&N air intake system to remove the intake restriction.
Gut the 2nd cat to remove the exhaust restriction.
Put in a TurboTech engine mount to 'plant' all the power.
Then have some fun...

 

Very true on most of what you state except 2 things.

Warranty. That is why I went with the GMTU kit. Doesn't void the original car's warranty.
The kit now has the plug-in harness'. No more hacking up the wires to splice in the new plug ends.

 

Still not worth it.
Our cars are older now, & going out of warranty soon anyways.
Warranty was really needed, to fix the dealer screw-ups, with putting the sensors in.
Some stealerships, would probaby deny most warranty claims, anyway.

2 of the best LNF 'tuners' over on CobaltSS.net
Chevycobaltss3 - James
Terminator2 - David

 

Stage 1 kit is a gmtune and 3bar maps which for the stock turbo not need anymore because hptuners has done a awesome job unlocking alot of tables. Only time you need the 3bar maps is if your going bigger turbo. The GMtune is not that great anyways you still get KR with it. Which you would think they would be perfect since the have the software to make it awesome.

 

Ok I see that now; its referred to as the Performance Turbocharger Upgrade Kit on the GM Performance Division website also. But they quote the 340 torgue I mentioned. You may be right, that the real world number that most people are getting is 315 torgue, but I was only noting what I saw. Still a nice increase.

That is great that you get better gas milage as long as you dont get in the boost territory. However that is odd to me that it would increase with a more powerful engine. Also, I noted that premium fuel is recommended. Are they referring to 93 or 92 octane. Ive been driving with 92 octane and the car runs great on it with great MPG.

As for not using this upgrade and useing an after-market. I would definatley be using the GM one if I do the change. I have a 2010 with only 16,000 miles on it. Warranty is important in this case.

 

If you do it, remember to get the harness, and keep the wires away from the condenser, when the direction of it is rotated there isn't much room. My dealer put this in to keep it back.

 

The 340 torque is for either the Soltice or Sky,can't remember which. The HHR SS kit is 315 torque.I read this elsewhere ,just not sure where. But I'm positive it said 315 for the HHR SS.
As far as octane.92 or 93 is fine.
Gas mileage? I'm guesing the upgrade kit "leans out" the engine a slight bit to obtain more power. Lean it out a little, get a little more mpg's. I have noticed my tailpipe doesn't soot up as much as before the kit.

 

The GM kit says 290HP and up to 340 lb-ft of torque. That however, depends on what car the kit is going into besides the HHR. The Cobalt, Solstice and Sky like Firemangeorge indicates. You can find that info on the GM Performance Parts info about the kit. The Solstice/Sky manual trans are the only motors that go to the 340 lb-ft number. The plug in adapter cables should make installation much more trouble free. However, the proximity to the AC compressor needs to be watched and minimized by varios means such as that shown by SS Fan. The IC can be shimmed, hoses trimmed to pull back the charge pipe or brackets. I chose the kit because of the warranty as well, but unfortunately had to suffer through the dealer fixes before the plug in kits came available. Good luck, and yes the car drives better and the mileage does come up a bit, but the tire mileage goes down ! By the way, If you do go the GM way with the power upgrade kit MAKE SURE that the dealer does not use an older kit with the crimp connectors INSIST AND CHECK that they will install the new plug in version.