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DP testing, the Ruthless Pursuit of Power

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Old 10-30-2012, 09:55 PM
  #41  
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Originally Posted by 2005HHRauto
Yes, of course, they cause the car to smell like a car from the 70's,
& don't have that nice throttle response, like the single factory DP.
So your saying I'll make better time with a single cat?
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Old 10-30-2012, 10:27 PM
  #42  
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Originally Posted by foolmoon_design
So your saying I'll make better time with a single cat?
No, just better all around town , throttle response.
It's has something to do with that 1st cat position.
There are 100s of tables in the ECM, that we can't see.
I Believe that the 1st cat is providing just enough back-pressure,
To make the ECM very happy. Resulting in better tip-in throttle response,
& all around better street manners. It least with an automatic.
It just feels so much better, with that 1st cat in place.
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Old 10-30-2012, 11:39 PM
  #43  
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Originally Posted by firemangeorge
No offense here folks, but I'm seeing very small square holes and nothing on the top of the pipe. Looks nothing like the picture posted.
Just to be sure, we are talking the muffler at the rear bumper?
I'll try to get a picture but doubt it will show up.
Hmmmm, mine has em on top and bottom....double-you T eff
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Old 10-31-2012, 08:13 AM
  #44  
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Originally Posted by XtremeSS
Hmmmm, mine has em on top and bottom....double-you T eff
Square, or round...
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Old 10-31-2012, 08:53 AM
  #45  
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Would there be any possible benefit (no loss?) with a 4" custom downpipe? My buddy did a 4" dp on his STI and ran a cutout---- most incredible turbo whistle ive ever heard! I know the k04 isnt a loud whistling turbo but it might make a better noise.
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Old 10-31-2012, 03:01 PM
  #46  
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Originally Posted by XtremeSS
Hmmmm, mine has em on top and bottom....double-you T eff
Once again I have to correct myself. Yes, mine does have that second double row on the top of the pipe. Found them by sticking a piece of wire up there and "feeling around". I guess the flashlight wasn't hitting them at the right angle.
And as 2005HHRauto said. There is a lot of soot up in the tailpipe.
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Old 10-31-2012, 05:38 PM
  #47  
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Originally Posted by 2005HHRauto
Square, or round...
They appear to b square...

Question- have you had a chance to compare auto and manual DP? Wondering if there is any other difference other than the length.
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Old 10-31-2012, 06:43 PM
  #48  
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Originally Posted by XtremeSS
They appear to b square...

Question- have you had a chance to compare auto and manual DP? Wondering if there is any other difference other than the length.
Ha, I never had a 2010 muffler apart, but why square holes...
Manual & auto DPs proformance , is the same.
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Old 11-01-2012, 12:35 PM
  #49  
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Could the difference be the year instead of the type?
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Old 11-01-2012, 08:56 PM
  #50  
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I think you said somewhere on here that you are using the factory exhaust from the Downpipe back. Did you try any other exhaust systems or mufflers to SEE if they offered a performance gain? I uunderstand that they may offer more noise but, like you, I’m not interested in noise.

I use to work for a major exhaust manufacture and I know that sound does not always mean more power

I am after the best all around performance with the least amount of sound. I've had the loud and now at my age I like um fast and quite. I don't mind a little more sound IF it means some additional power and thanks again for all the great info you are sharing.
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