For those who put on a header/manifold...
New Member
Joined: 10-21-2006
Posts: 11
From: Delta
I was originally looking at that, but from what I read at the Cobalt site, the high flow cat creates a lot of extra noise. I'm walking a line with my wife's car and I gotta be careful, I would love to hear the difference it makes. That's why I'm probably heading to tunetime for the Cobalt dyno day, that'll help if I can hear this mod first hand.
Senior Member
Joined: 05-13-2006
Posts: 2,334
From: Chicago,IL
I have never known a veh. with headers to be quiet or as quiet as an original manifold, if you think this is gonna bother the wife, I`d leave it stock (non-headers).
Driving a car daily, with the additional noise, is gonna take some getting used to...
Driving a car daily, with the additional noise, is gonna take some getting used to...
Senior Member
Joined: 12-18-2005
Posts: 1,791
From: Middle Village, NY
I thought that too little back pressure would hurt performance. Unless the header's equal lenght tubes make all of the cylinders have equal flow.
In other words, what would I gain putting it on my HHR-I have the CGS with outlaw, Autolite plugs, Imco muffler, and TuneTime computer. Would I need the down pipe also, and together would they just bolt onto the rest of the stock setup? Noise is a non-issue (infact, I would look forward to the balanced header sound).
In other words, what would I gain putting it on my HHR-I have the CGS with outlaw, Autolite plugs, Imco muffler, and TuneTime computer. Would I need the down pipe also, and together would they just bolt onto the rest of the stock setup? Noise is a non-issue (infact, I would look forward to the balanced header sound).
Senior Member
Joined: 05-26-2006
Posts: 249
From: Montreal, QC. CANADA
It not a HHR(The Z, my other baby...), but here what it sound with Header + Hi-Flo cat + Cat Back Magnaflow 2.25``all hook up to the 2.2l Ecotec, I want to install a resonator on the line, to have a better roar sound...
Here from the garage, still cold, better when the engine is very warm hot...
Click here to see Video
Click here to see Video
Somewere in my town....
Click here to see Video
Here from the garage, still cold, better when the engine is very warm hot...
Click here to see VideoClick here to see VideoSomewere in my town....
Click here to see Video
Senior Member
Joined: 12-21-2005
Posts: 1,010
From: Launch Coast Calif.
Here is a thread I started last year..
again Use Cobalt Addition Header, high flow downpipe cat..
I have the Gibson Cat back exhaust also..
Lots of torque.... zooms up hills, pass other 4 cylinders, and some V6's
Senior Member
Joined: 06-21-2006
Posts: 3,100
From: Chicago
Cobalt Addiction is a good header for the NA cars like the 2.2 and the 2.4 because it's opening is only 2.5" which makes for better torque. Definately a good purchase. It will make a really good difference on your HHR! Expect around 10 horses at the wheels on average for this header. Their price is really good too. You really don't want anything bigger than 2.5" on the NA HHR.
If you don't have an exhaust system yet I suggest the following....
1. Cobalt Addiction header
2. 2.5" Downpipe with highflow cat
3. 2.5" Mandrel bent exhaust with a resonator and free flowing muffler
It may be a bit louder but you can also find mufflers that have removeable silencers that will take the exhaust tone from loud to almost non-existant. Just my
. Others on here will suggest alternatives like keeping all your stock piping, or not going any bigger than 2.25". However, changing the pipe diameter by .25" may not seem like much but with the 2.4 engine you will not lose as much of your torque as you would gain from the top end horsepower. Local guys here with Cobalt SS 2.4's are running 2.5" and they noticed quite a bit from their cars.
If you don't have an exhaust system yet I suggest the following....
1. Cobalt Addiction header
2. 2.5" Downpipe with highflow cat
3. 2.5" Mandrel bent exhaust with a resonator and free flowing muffler
It may be a bit louder but you can also find mufflers that have removeable silencers that will take the exhaust tone from loud to almost non-existant. Just my
. Others on here will suggest alternatives like keeping all your stock piping, or not going any bigger than 2.25". However, changing the pipe diameter by .25" may not seem like much but with the 2.4 engine you will not lose as much of your torque as you would gain from the top end horsepower. Local guys here with Cobalt SS 2.4's are running 2.5" and they noticed quite a bit from their cars.Jason
You Are Da Man
Senior Member
Joined: 06-21-2006
Posts: 3,100
From: Chicago
It not a HHR(The Z, my other baby...), but here what it sound with Header + Hi-Flo cat + Cat Back Magnaflow 2.25``all hook up to the 2.2l Ecotec, I want to install a resonator on the line, to have a better roar sound...
Here from the garage, still cold, better when the engine is very warm hot...
Click here to see Video
Click here to see Video
Somewere in my town....
Click here to see Video
Here from the garage, still cold, better when the engine is very warm hot...
Click here to see VideoClick here to see VideoSomewere in my town....
Click here to see VideoOutstanding
Z-Man
Thread Starter
Senior Member
Joined: 05-26-2006
Posts: 732
From: Pottstown, PA
https://www.chevyhhr.net/forums/show...ghlight=header
Here is a thread I started last year..
again Use Cobalt Addition Header, high flow downpipe cat..
I have the Gibson Cat back exhaust also..
Lots of torque.... zooms up hills, pass other 4 cylinders, and some V6's
Here is a thread I started last year..
again Use Cobalt Addition Header, high flow downpipe cat..
I have the Gibson Cat back exhaust also..
Lots of torque.... zooms up hills, pass other 4 cylinders, and some V6's
I bought the Cobalt Addiction Header, because I knew you made it work, but there is a problem. My mechanic bolted it up jut fine...then noticed that there was a leak from the coolant line running behind the engine. The header tube for the #4 cylinder (driver's side) touched the coolant line just enough to cause it to leak at the "o" ring. Did you have this problem, and if you did how did you overcome it, I don't want to dimple the header if I don't have to, that could make things worse.
Please let me know, thanks.
