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10-31-2009, 07:03 PM | #1 |
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Stock Rear Section with Akra Mid-pipe Dyno & Vid
I just had the Akrapovic mid-section (X-pipe and high-flow cats) installed with the stock rear section. EF1 Motorsports in Signal Hill, CA, did the install, with Chasen from Dynotech handling the dyno pulls before and after. [Thanks, guys!]
I didn't get the image from the "After" dyno runs, yet, so I apologize for the minor tease. I will post those as soon as I receive them. Experts feel free to chime in about the "Before" traces. UPDATE: I've added the "After" dyno runs and the comparison plot. The modification netted me 14.5 HP and 12.1 lb-ft of torque. I'm still deciding on what rear section to get, so the car has not been tuned to fully take advantage of the new installation. The car now has a racier (not ricey-er) sound at higher throttle openings, but there is no drone that I can hear at any RPM or throttle opening. It just sounds a little more aggressive overall, both inside and out. My memory of the full Akra system was of a quieter sound than this setup overall, which is a bit of a surprise. Anyone out there have just the Akra axle-back that thinks it is quieter than stock? Last edited by slipstream; 11-11-2009 at 10:27 PM.. |
10-31-2009, 10:49 PM | #5 |
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Numbers look great bud, especially given how low-reading that dyno is .
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10-31-2009, 10:52 PM | #6 | |
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I am keeping the stock pipes in case I have trouble with smog 3 years from now. I haven't gotten the CEL yet, but I'm sure it will happen sooner or later. Akrapovic is supposed to be working on a fix. |
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11-01-2009, 01:28 AM | #8 |
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I don't want to misspeak on the numbers, so I'm waiting until I get the other dyno graphs. It wasn't earth-shattering with no tune. Like I said, sorry to tease, but I thought they had sent me both sets of plots. I will post as soon as I have the graph.
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11-01-2009, 05:06 AM | #9 |
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11-01-2009, 06:28 AM | #10 | |
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11-01-2009, 06:29 AM | #11 |
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First things first!
First I want to congradulate slipstream on his amazing X-pipe and review!
Second I think Akrapovic X-pipe is the highest quality product money can buy! Third Engineered to work together maybe? The rear section is TUV approved which means quiet and somewhat restrictive. Not much more sound when installed with stock x-pipe. Fourth I had this setup mated to an Active Autowerke rear section which was mean and agressive; I felt alot more power in the midrange compared to Akra rear section and alot better sound. |
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11-01-2009, 10:30 AM | #12 | |
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Like you mentioned, the Akra slip on is around the same db level as stock to keep it within TUV & I'm thinking one of the best performance oriented exhaust packages you can buy and stay within noise standards, agree? Not sure if there are many others out there that can match the weight reduction & gains. Of course it comes at a price - I'm an Akra fan - Just haven't made the plunge yet. Maybe in the spring after more R&D is done - |
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11-01-2009, 12:56 PM | #13 |
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11-01-2009, 03:07 PM | #14 |
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I thought Akra didn't sell the x-pipe separately, has that changed?
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11-01-2009, 04:29 PM | #15 |
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11-01-2009, 05:22 PM | #16 |
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11-01-2009, 06:00 PM | #17 |
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You can now buy the Akrapovic X-pipe separately
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11-01-2009, 06:51 PM | #18 | |
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if it makes you sensitive guys feel any better, i'll be pairing the exact opposite (Akra Rear + OEM Mid) then pairing it later with an AA Mid or Fabspeed Mid.
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11-01-2009, 09:04 PM | #19 |
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This modification was an experiment, and as such, I don't feel offended by negative comments. Exhaust sound is a personal preference. It does sound a little raw and unfinished.
I plan to buy something to replace the stock muffler at some point. From what I've read, the mid-section is where you get the most power gains, so I was curious what kind of results I would get. I expect there are others on the forum who share my curiosity. It's all good. |
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11-02-2009, 06:02 PM | #20 |
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The dyno operator was shifting way too early which is what made it sound so bad. The actual pull sounded like a race engine.
I think it's the stock muffler - it's tuned for the OEM midsection. My car sounds a little "off" with the fabspeed resonated xpipe and the stock muffler at low speeds and high load. The thing sounds absolutely amazing at 4k plus though. I would guess you get similar, but not identical, sound with all the aftermarket xpipes. Thanks for posting this for the forum! |
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11-02-2009, 09:36 PM | #21 | |
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11-02-2009, 10:33 PM | #22 | |
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How was it in the morning when you're leaving the house? Some get kinda boomy and are very loud at initial start up.
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Let me get this straight... You are swapping out parts designed by some of the top engineers in the world because some guys sponsored by a company told you it's "better??" But when you ask the same guy about tracking, "oh no, I have a kid now" or "I just detailed my car." or "i just got new tires."
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