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HHR Resonated Cat Bypass Installed!

 
Old 04-13-2016, 01:52 AM
  #1  
luvmy356
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Default HHR Resonated Cat Bypass Installed!

I finally pulled the trigger and installed a Hanksville resonated cat bypass today on my 6MT GTS. I was hesitant as I wanted a resonated bypass (and didn't know HHR offered one till recently) and I read about the challenges of removing the top bolt on the passenger side. I wish I would have done this sooner. It still too quiet for me at idle, but sounds great the rest of the time.

Here are some pics of the install. I will work on a road video when my GoPro is returned next week.



This is where the secondary cat connects to the downpipe. The top bolt is out of sight. There is no room to get a wrench on it from below.



With the transmission subframe removed you can drop the secondary cat which gives you some access space to get to that bolt. You can see a 3/8" ratchet connected to a 1/4" 12mm socket with short wobble extender and adapter in the pic. I had just enough room to hit the ratchet with a hammer till the nut broke free. I tried a flex head wrench and a universal joint socket but couldn't get enough torque to break the nut free



A comparison of the old and new. The exhaust hangers still need to be switched over from the old pipes to new brackets which then get bolted to the tabs on the resonators



Both sides installed with the transmission subframe back in place and hangers connected.
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Old 04-13-2016, 10:02 AM
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bweSteve
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nice.

Hockey Pucks. No good garage should be without a few to be used as chocks!!

=Steve
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Old 04-13-2016, 10:42 AM
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westsiderkg
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How about a sound clip?
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Old 04-13-2016, 11:22 AM
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Brit6
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What was your reason for wanting resonated pipes instead of the straight throughs like the fabspeeds?
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Old 04-13-2016, 11:49 AM
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luvmy356
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Originally Posted by Brit6 View Post
What was your reason for wanting resonated pipes instead of the straight throughs like the fabspeeds?
The examples I heard on Youtube with a straight by-pass had a raspy/metallic note added to the sound. I was hoping the resonators would mellow that tone while uping the volume.
Originally Posted by westsiderkg View Post
How about a sound clip?
I'm borrowing a GoPro today and will work on a sound clip. We'll see if my sound is less raspy with the resonators. There is already a youtube clip of another GTS with a resonated bypass and the sound is different than the straight pipes.
Originally Posted by bweSteve View Post
Hockey Pucks. No good garage should be without a few to be used as chocks!!
=Steve
I don't play hockey but the pucks are my most used tool in the garage. They are great when lifting on a body seam or anywhere that you want to protect.
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Old 04-13-2016, 03:48 PM
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If you record a sound clip how does it compare to the sport mode? I thought sport mode was plenty loud with the stock exhaust, while driving.
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Old 04-14-2016, 02:39 AM
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With the stock setup, I thought sport mode was only a little louder than normal mode. With the cat bypass, its really obvious now when the car is in sport mode. Light acceleration you can hear it, and cruising on the highway you can hear it. On the highway the extra rumble is not too bad and when sport was switched off, it was just a quiet as before the cat bypass. The only time it got loud in normal mode was during hard acceleration, otherwise it was just like stock.

I did make a recording and uploaded it to Youtube. It has a lot of background noise which I apologize for. And after listening to it, I'm not sure if the resonated version sounds any different than a straight cat bypass. In the video, you can hear the brappy sound which I thought could be minimized with the resonators.

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Old 04-14-2016, 01:37 PM
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Thanks for the clip!!
Sounds great, not raspy at all and there was some burble while decelerating.

I tried getting the info from HHR's yesterday but their site was down. Will try again today.

Last edited by v10rick; 04-14-2016 at 01:57 PM.
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Old 04-14-2016, 07:14 PM
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i actually got them to post up the resonated pipes again. i haven't pulled the trigger yet but had a few questions;

1. any raspiness or metallic rattling sounds?
2. how is it on cold start?
3. any metal or raspiness at WOT
4. total cost?
5. thoughts? drone? interior sound? I do not have a GTS i have the 957 S
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Old 04-14-2016, 07:16 PM
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Originally Posted by v10rick View Post
Thanks for the clip!!
Sounds great, not raspy at all and there was some burble while decelerating.

I tried getting the info from HHR's yesterday but their site was down. Will try again today.
This is the same leistung motorsports resonated pipe. Hanksville bought LMS and now put their badge on the LMS pipes, both regular and resonated.
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Old 04-14-2016, 08:13 PM
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Originally Posted by zonnie View Post
i actually got them to post up the resonated pipes again. i haven't pulled the trigger yet but had a few questions;

1. any raspiness or metallic rattling sounds?
2. how is it on cold start?
3. any metal or raspiness at WOT
4. total cost?
5. thoughts? drone? interior sound? I do not have a GTS i have the 957 S
I don't think there is a raspy or metallic sound but there is a definitely a brrap brrap sound at WOT you can hear in the video. At partial throttle, just a nice extra rumble. On a highway cruise, its there is an additional rumble, but no drone. This is with the muffler in sport mode. When the muffler is in normal mode, its just as quiet as stock, except at WOT when it sounds like the sport mode got turned back on.

On a cold start, there is a quick bark then it quiets down. It sounds like the start in the first few seconds of the video

HHR sells the resonated pipes on their website for $595 plus shipping which was $30 for me. I installed them myself so that was my total cost.

I am happy with the upgrade and the customer service at HHR. Hank was always responsive to my email questions.
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Old 04-15-2016, 01:07 AM
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I wonder why HHR blogged back in Jan 2015, that they would add 958 products to their website, and it's now 1.4 yrs later, and they have not.

http://www.hhrproducts.com/blog/happ...-958-exhausts/

http://www.hhrproducts.com/blog/tag/958

http://www.hanksvillehotrods.com/Hom...9/Default.aspx

unless I'm missing a weblink somewhere...

even looked thru Facebook pages (which btw, I really do NOT enjoy FB)
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Old 04-18-2016, 01:23 PM
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Originally Posted by bweSteve View Post
I wonder why HHR blogged back in Jan 2015, that they would add 958 products to their website, and it's now 1.4 yrs later, and they have not.

http://www.hhrproducts.com/blog/happ...-958-exhausts/

http://www.hhrproducts.com/blog/tag/958

http://www.hanksvillehotrods.com/Hom...9/Default.aspx

unless I'm missing a weblink somewhere...

even looked thru Facebook pages (which btw, I really do NOT enjoy FB)

probably best to email Hank, he seems pretty reasonable via email and replys pretty quickly.

I had to email him about the resonated pipes then he put them online and notified me via email couple weeks ago.
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Old 04-19-2016, 03:32 PM
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Those look nice.

I just installed the Fabspeed Secondary Cat Bypass pipes on my '09 TTS this past weekend and can attest to the fact that the top bolt on the passenger side is an SOB - worked on it for probably 60-90 minutes with every wrench, ratchet, U-joint, extension, etc I have in my arsenal. I was finally able to get it free with a GearWrench angled ratchet wrench that has the swiveling ratchet end. You could get it around the nut well, but the angle it had to be on made for virtually no leverage. I finally pulled down on he braided section of the pipe a bit and put the wrench on from the opposite side of what seemed logical and correct and found just enough leverage to break it loose.

During reassembly I used stainless deep M8 socket cap bolts with Marine grade anti-seize on them and that one bolt I put through from the top side with the nut on the bottom. I was able to get a metric allen wrench into the top of the bolt cap and hold it with a vice-grip while I tightened the nut with the GearWrench.

Glad I like the sound as I don't want to put the original cats back any time soon.
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Old 04-19-2016, 04:42 PM
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What I can't get a solid answer on is this:

How does the cat bypass sound in normal, non sport mode, to the stock exhaust IN sport mode? Louder? quieter? similar? Obviously they'll be louder comparing sport to sport, and that's perfect.

That rapping at WOT can probably be calmed down with a full size X pipe instead of the H pipe but you may not kill it totally.
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