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Cheapest / Loudest / Low-Drone exhaust option found!

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So I recently purchased a 2007 Boxster and having just came from a fire-breathing Corvette I was looking for a good exhaust option to replace the anemic factory exhaust. Mine is the 2.7 base without the PSE.


After finding that cat-back exhaust systems for the 987 were ridiculously priced I set out to see if I could build something that could give me what I was looking for: fairly loud (the Corvette was very loud), low to no cabin drone, and an aggressive sound. Thus begins my journey. 


I started by removing the factory exhaust just after the first set of catalytic converters:








Then I had some muffler delete pipes fabbed up and simply attached them to factory tip. The exhaust hangers were some that my local shop just had laying around that happened to work perfectly in the factory location - they just utilize the two lower mounting bolts:








I drove it this way for about 2 weeks - it sounded mean as hell - but it had awful, mind blowing, forget-about-having-a-conversation drone and between 2-3k rpms under moderate acceleration it also had an equally awful raspy tone. So, I started looking for a solution ... and I found it!






These are exhaust inserts (baffles) made by a company called Car Chemistry. Now, without sounding like too much of a sales pitch from these guys, these little things are awesome. I spoke to the owner Ken who was extremely responsive and helpful and I decided to give it a shot since I really had nothing to lose (I'd only put about $100 into the project at this point). Here they are installed:





If you look closely you can see them in there. These were installed right where my muffler delete pipe gets welded onto the factory exhaust (again, just after the factory cats).


I can honestly say it's cut drone 75% in the cabin - it's no worse than what I can imagine all of the other aftermarket exhausts produce - if not less judging by what I've heard about Borlas (with exception of course of the even-more-ridiculously priced ones). It has completely removed the nasty-raspiness. And it only took about 25% of my out of cabin noise away.


The car honestly sounds ferocious now - clean and exotic all the way through the rev band regardless of throttle application.


The best part - total spent for entire exhaust including labor: ~$200


I'll be posting up some pictures of the final setup installed on the car, sound clips, and decibel readouts either tonight or tomorrow morning but I can honestly say I'm 100% satisfied in the results.


Note that should you try this, it's not for the faint of heart. While it's not as loud as my Corvette or dozes of other cars you see on the street you still get a nice doppler effect as you pass other cars - it definitely turns heads but in a good way. Since I've been running this setup I've had numerous people come up and ask me what I had done to the car - their face when you tell them you're running straight pipes is priceless.


As always, comments welcome.

Edited by jnance50
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Video! This does not do it justice - the idle doesn't sound so "boat like" in person and it's not as "airy" - working on a drive-by.

I was initially concerned with flow as well, but from all of my reading on these it doesn't seem to be a huge issue based on dyno numbers provided from other vehicles. The restriction from the inserts seem to be less than that of the factory exhuast. If anything, it added some back pressure back that I had lost from the straight pipes.

I will try and get to the Dyno next week and see how it does. Edited by jnance50
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I personally think that sounds awful but each to their own.


Yeah, I do need to find a more accurate recording apparatus. I know everyone says "the video doesn't do it justice", but that's really the truth. If you listen to the rev - that's a more accurate representation. From the video the idle sounds like a farm tractor - in person it sounds a lot more refined. I'll try and get a video with a different camera tomorrow.

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  • 2 weeks later...
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I lost significant power when I replaced the stock exhaust on my '01 S with a custom catback with tiny bullet resonators. It did take a bunch of weight off and sounded awesome.  Unfortunately the drone at freeway speeds was terrible!


Baseline vs exhaust only



Added an EVO CAI.  That made things a LOT better!


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