I've been reading through the threads here, and haven't found a whole lot of discussion on the cat-back options for these cars. Mitzi has finally decided she thinks her surfer girl sounds too "laid back" and has OK'd the idea of dropping in the CGS intake and a cat-back system.

Research of the vendors here show that both Borla and Magnaflow make off-the shelf cat-back systems for the HHR's. Also, I've contacted Zoomers down in Irvine who said they could custom-build pretty much any cat-back system I could imagine and would be happy to take a look at the car for not much of a premium to build and install a new cat-back system vs an off-the-shelf non-installed system. (A number of the LX crowd swear by Zoomers) Seriously considering having them build a dual-exhaust for it.

If I stick with the off the shelf systems, has anyone heard the two? any comparison??

 

Any cat-back you install on the HHR is going to be very, very loud compared to stock - with a lot of resonation inside the cabin at highway speeds. My car was used to prototype several of the systems (we also sell the Gibson system here), so I know first hand.

For a nice healthy sound, I recommend just swapping mufflers to the IMCO 924 - it sounds healthy without all that "ricer" resonation.

Just my - I'm sure others will chime in soon.

Be sure to ask respondents if HAVE the system on their HHR!

 

i think thats one of the most important things for me... i HATE that crap

 

I went the IMCO route first and was very happy with it.

I wanted functional side pipes though and because of the issues try to route anything in the rear, the IMCO had to go.

First I had all from the cat back taken off and used a Thrush where the resonator was with a "Y" pipe coming off of that to the side pipes. I used dual pipe tips on each side by Walker. As Mike said it WAS VERY LOUD!!!

I've since added two small resonators by Walker between the "Y" and the side exhaust tips. I am VERY HAPPY!! It is not near as loud as the Thrush by itself, but is still louder than the IMCO. I can't really speak on performance good or bad yet, not enough miles with the system installed but so far it seems to be performing well.

This has not been an inexpensive install. I hoped I could find an easier/cheaper way. The only easy/cheap way is the IMCO. (Remember I did say I was very happy with it.) I really wanted something a little more unique.

 

I didn't go cat back, I just replaced the muffler to a RS 4" straight through outlet, VERY loud, but deep and throaty, nice the pissed off weedwacker sound. Also a good feeling gain.

 

 

with the IMCO your only going half way with a mod..

a full cat back system is the way to go.. I have the Gibson Cat back...

 

Not really true. The stock HHR exhaust is 2 1/4" mandrel bent tubing - there's no need for anything larger. Any good engine builder will tell you that 2 1/4 is good for at least 250hp of flow without any problems. I've had the Gibson on my personal car (we sell them), and can vouch that mine runs much better with the IMCO installed than a full cat back system. Better mileage too.

The cat-backs make more noise (and a LOT of internal cabin resonance at highway speeds), but lose a lot on the low-end. Perhaps they offer a tiny bit more when the car is fully tapped out - but most people don't drive that way.

Of course, everyone has their own opinion of what's fast and what's loud/not loud.

 

is the mangaflow cat back loud!

 

Use your own judgement, search other sites...
You will notice most change outs are for the entire system not partial...

Again according to your budget, performance needs, etc..
make your own choices..