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Borla manifold and Random Tech cat !

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Hello fellow Subaru-lovers :)

 

 

My 10 year, and two month, 185,000 mile old Impreza was getting ready for a new exhaust, so I decided it was time for a little upgrade and ordered a Borla manifold and a Random Technology catalyst. Good thing too, just in the nick of time....the stock cat pipe c-r-a-c-k-e-d the very day before my new piping arrrived :rolleyes:

 

Anyway, it's all in place now, fitted neatly, no fiddling about...I have had some VERY BAD experience with a Hayward & Scott system, that didn't fit.

 

I have to say, I am very impressed with the quality of these American products :clap: Beats "English Craftmanship" any day. In fact, I am so pleased, I have ordered the full cat-back system too :slobber:

 

(Don't forget...I am a Dane, living in Denmark.)

 

 

 

Oh yeah, a few pictures for your viewing pleasure:

 

 

Borla_Random.jpg

 

RandomTechCat.jpg

 

JointMidPipe.jpg

Whats with the 3 pipes on one side?

 

Something I'm missing here. :lol:

 

But it's so shiny!!! Shiny = good.

  • Author

3 pipes...thats because the headers from each port are quite long. So the left most pipe of the 3 side by side in the picture is the collected pipe from the left head, running parallel to the 2 header pipes from the right ;)

 

So it merges 4-2-1.

 

 

With the Borla and the rotting old cat-pipe on, the sound was very relaxed, kinda five-cylinder like. After fitting the free flowing Random Tech, the sound is a bit louder, but also more agressive. But only really on acceleration, and expecially at WOT. Cruising is surprisingly quiet. Most the noise now flows out the back, so overall the cabin is more sedate than with the stock manifold/cat setup and my open rear muffler.

 

The Borla cat-back system is on it's way to me, will be here Tuesday, I expect this will be quieter than my "Jama" muffler.

 

 

G-Tech road measurements show an average 2% increase in peak horsepower, but 4% mid-range. A surpise for me, since I thought this system would make the power delivery peaky, but it has actually lifted the torque curve in the 3000-5500 rev band :brow:

 

 

(I quote percentages since my weight is estimated. Multiple runs were done in both directions on the same stretch of road, in the same weather conditions before and after fitting the Random Tech. Fuel tank was brimmed at a nearby gas station, for both set of runs.)

I want to see a video.

 

Little warning. A lot of people have had issues with Borla headers cracking. Hope you don't have the same luck.

  • Author

Yes, the cracking is something I have heard about. That is why I have bought the manifold from a local dealer, and not via the internet. I will have somewhere to go, IF something goes wrong.

 

I have also kept my original manifold, so the car won't have to stand still during a warranty claim.

 

Still, reading around the net, it seems like the cracking has been solved. Most complaints are many years old. My manifold was built in December 2009 according to the paperwork, so I would expect that Borla has solved the problem.

 

Surely, some cases of cracking could be due to worn engine mounts? Which would not even be Borla's fault?

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