Now, if this topic has already been covered, or beaten to death in the past, please accept my apologies.

Ok, I just noticed that the Stage-1 kit shows higher HP and max torque for the HHR and Solstice Sky.

What is the reason for the lower figures for our cars?



This is what I found. Please see below:

Cobalt 2008-2010 HP & Torque ratings:
280HP @ 4,700 RPM
320 lb,-ft of torque @ 4,300 RPM
Kit disables "learn down feature"
This performance upgrade maintains no-lift shift feature on Cobalts and HHR's and adds it for the Solstice/Sky.
Note:

Solstice SKY HP & Torque ratings:
290HP @ 5,200 RPM
MT 340 lb,-ft of torque @ 3,600 RPM
AT 325 lb,-ft of torque @ 3,600 RPM

HHR HP & Torque ratings:
290HP @ 5,200 RPM
MT 315 lb,-ft of torque @ 4,800
AT 315 lb,-ft of torque @ 4,800

19212670 Performance Upgrade Kit for Cobalt, Solstice, GXP.SKY, HHR
Applicable: 2007, 2008, 2009 Solstice GXP/SKY RedLine, 2008, 2009 Cobalt 2008, 2009, 2010
Installation labor: not included. Guideline is 1.2 hr for the Solstice/Sky, 2.0 for the HHR & Cobalts.
Premium fuel is REQUIRED with this kit.
This performance upgrade enables no-lift shift feature on Solstice/Sky. NLS is already included on the HHR and Cobalt.
This kit needs to be installed by a dealer and reflashed by the dealer. It does not void any warranties.


What's in the box:
1 - Bolt Tmap Sensor
2 - Connector Sen-MAP w/ leads
1 - Sticker Premium Fuel
1 - Label Cert
2 - O-Ring T-MAP
2 - Sensor T-MAP
1 - GM Performance Decal
1 - Instruction Sheet



Ok, I;m done.....Old Veteran Car Dude

 

Here is what GM HPVO's Bill Duncan had to say about the differences in the HP and TQ between the Cobalt and HHR SS.

 

^ Hmm, that's interesting stuff right there, thanks!

Later
Allex

 

NP 8) The HHR SS's stock air box is pretty cool IMHO. Dosen't your HHR come with a K&N type cone filter from the factory? I was looking at the K&N intake and they leave alot of the factory air intake in place except the Lid and the air box to turbo tube ....... GM must have put some thought into that airbox 8)

 

what about the difference on the soltice/sky? they are rated even higher than us with cobalts

 

I was aware that the airbox caused the discrepancy; not so much that the flex section was the main reason. Not sure about the Kappa cars just figured it was related to the rwd layout

 

ummm......the hhr has a flex section coming right off the turbo

 

Sort of. It's a paper filter but it's shaped just like a K&N unit. K&N's intake basically removes the "pancaked" section of the tube that goes to the turbo and smooths it out, it's essentially the same diameter though.

Later
Allex

 

Good info, i was wondering that also.
So does that mean with a hahn or other a/m intake with GMS1, the horsepower should be higher than the spec, but max torque will stay the same?

 

I'm not sure how GM stage 1 reacts to an intake .... but i do remember when GM was talking about stage 2 for the Cobalt ....... All it was going to consist of was a GM air intake , so to me that says the stock intake is a restriction .

 

Did GM ever make a Stage II upgrade for the Cobalt SS turbo?

Old Veteran Car Dude

 

Nope

Also the HHR SS has a shorter final drive than the Cobalt SS Turbo, so it has less load/less prone to breaking.

 

It has to do with the different intake and exhaust systems.

 

If the intake system lowers the restriction you will get increased horsepower & torque depending on how much the restriction is reduced and where in the flow curve the reduction occurs.

 

i read like someone stated previously that the stock cobalt airbox was the problem and more specifically the flex section of the cobalt