Saturday, July 6, 2013

Help from a BRZ

In February of 2013, when I installed the SPT Catback Exhaust at Russ' Garage, there were two things that I really loved that kept me going: the Look and the Sound.  However, there were setbacks that I hadn't taken into account until the exhaust was on there and I had been driving it for a couple of weeks.  Interior Cabin Noise, loss in low-end torque, and (as a result of that loss) significantly worsened performance and gas mileage.  I had initially thought to solve at least the cabin noise with a resonator install, but the performance issue would still be nagging at my fuel gauge.  Thus, I started brainstorming for an alternative exhaust setup.  I figured I wouldn't be able to retain all that wonderful SPT growling, but I wanted to at least retain the look of the quad tips on the back of my Impreza.  That's where an unlikely hero stepped in to help me solve things... the Subaru BRZ.


Once again, Russ' Garage was the go-to place for this project.  Thanks to a fellow enthusiast who had just installed a Perrin Exhaust onto his BRZ, I was able to nab a stock BRZ catback exhaust and start working with that.  Russ laid things out and checked to see what could stay and what would need to be modified and got a simple solution set up.  The system would retain the stock Impreza mid-pipe up until a few inches ahead of where it clears the rear suspension.  From there, we cut the tail end of the BRZ mid-pipe to pair with the stock Impreza mid-pipe.  Then the hangers on the BRZ muffler linked flawlessly into the 5-Door Impreza's existing setup (like it was made for something like this) and buttoned the rest of the exhaust up!

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The next part really finished things off, though.  The tailpipes were too short to make it to the edge of the bumper... and I still wanted a quad-tip look that I had on the SPT Exhaust setup.  I tracked down lookalike exhaust tips from RedTail Performance, double wall, angled cut, polished chrome finish, and started cutting into my bumper to accomodate the space.  A good friend of mine with a WRX helped me weld the tips on to the BRZ tailpipes and, after finishing up the edge of the bumper with some crafty use of Door Edge Guard, it was finished!

This exhaust certainly looks the part.  It's integrated into the bumper, so not only does it look more like part of the car, but it's also brought back my stock ground clearance, which is helpful when I want to be a little more adventurous.  Thanks to the smaller diameter piping in the BRZ exhaust, there's no loss in power or low-end torque.  As a result, fuel economy has returned and I easily average 33mpg combined city/highway driving.  Cabin noise is nice and quiet again, so my passengers are thankful for that.  Overall, there's a long list of things I enjoy about this setup as it just makes more sense for a car like this.

While I have lost that fantastic head-turning rumble from the SPT setup, there is still a little attitude to this one.  If a loss in obnoxious sound is the only downside to this, I'd call that a win.

13 comments:

  1. This is a great look. Since mine is what I take to customer's shops, I do not want the obnoxious loud sound.

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  2. Any chance of a sound clip? Also, I know the folks over on NASIOC are waiting to hear the BRZ muffler too :-)

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    1. Honestly there's not much to hear. I suppose I could just video clip it to prove the point, but there's not much rumble with the BRZ muffler on there.

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  3. Did you have to change anything to fit those wrx wheels on? Or did you simply just bolt them on?

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    1. No changes made, though I did use a different tire size to get proper wheel diameter so as to not throw off my speedometer. http://allwelldrive.blogspot.com/2013/08/those-wheels.html

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  4. Just got a brz catback and I too own a 5 door impreza. Was wondering if it was necessary to cut the pipe from the brz and have it attached to the impreza or if I can simply just do a direct bolt on from the brz catback to the impreza midpipe without any modification. Been following you for a while, love the blog.

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  5. I also had a similar question about that, i saw that a lot of 2012 impreza owners are putting the BRZ muffler on but it is not an "Exact" fit. From what i saw, there is a little modifying that might need to be done to the Midpipe and the muffler In-let.

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    1. The second paragraph on this page pretty much spells out what I did. Didn't need to change the muffler at all. The BRZ Exhaust and Impreza Exhaust were welded together close to the point where the pipe passes around the rear suspension.

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  6. So to confirm your exhaust setup, all you used from the brz exhaust was the muffler, or part of the next pipe in line as well

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    1. As pictured, we used the stock Impreza mid pipe and rear portion of the BRZ mid pipe. You can see exactly where the two were connected in the pictures. The stock BRZ muffler attaches to the existing hangars under the hatchback.

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