01-04-2019, 07:15 AM | #23 | |
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OP is this something that's been done? Weight comparison on stock mid and AA mid? |
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01-04-2019, 07:20 AM | #24 |
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Yes 20 hp with dekat dps, 18 more with mid pipe and 17 with air intake, 55 hp without ecu tune LOL
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01-04-2019, 10:34 AM | #25 | |
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Unless you are accusing AA of cheating, im not sure what point you are trying to make? Instead of being sarcastic, i recommend you prove your point by showing a proof where the midpipe did not add any power.
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01-05-2019, 11:42 PM | #26 | |
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The stock system 2 by 3 inch pipes has a 50% higher flow capability. So more going on here with deletion of restriction which is not an apples to apples comparison. I make assumption here stock mids are 3. Thats impressively large. Over in M6g Mustang forum, the arguments are endless about cutting in H pipe sections into the GTs parallel mid pipes to achieve a low bellowing note, or inserting X pipes instead for slightly better flow but these can sound raspy at higher rpms. Any-one thinking of just putting one or more cross tubes between the two std parallel mid pipes to balance the note and achieve the single pipe tone claims but with a higher flow potential? |
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01-06-2019, 06:39 AM | #27 | |
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01-07-2019, 07:30 PM | #29 |
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How do you like the exhaust sound after installing the AA midpipe ?
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01-07-2019, 08:25 PM | #30 |
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Great have car parked winter so cant really enjoy it much but sound is much cleaner and deeper with some turbo spool noise. Bmw did a good job on the m2c's rear section.
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01-07-2019, 08:33 PM | #31 |
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Awesome
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01-08-2019, 03:23 AM | #32 | |
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AA s55 m/pipe is single 3.5" diameter or radius of 1.75" so CSA = 1.75 x 1.75 x 22/7 = 9.625 sq in CSA reduction of ~2% but this likely to be offset by less turbulent flow in large ID single m/pipe, compared to dual pipes, due to smaller circumference = less drag/friction at the interface where gas flows close to pipe ID surface.
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01-08-2019, 04:26 AM | #33 |
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Ah ha- thanks for correcting my calcs. I used dia not radius and as you indicate pipes are 2.5".
So the 3.5 " is smaller and with friction issue maybe line ball. So this alone isn't a driver of a power increase IMHO. An H pipe section added in may achieve similar note change. I liked the exh note of the demo I drove so not planning change on mine at this time Cheers Last edited by Muncher; 01-08-2019 at 04:29 AM.. Reason: Misread previous post |
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01-09-2019, 08:29 AM | #35 | |
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Overall volume is less but so is the overall friction with the smaller surface area. However, the main contributing factor to the power increase is the increased velocity. By mixing both banks almost immediately after the downpipe, we can take advantage of the Venturi effect as demonstrated below. This will promote high exhaust gas speed which helps reduce spool time and increase overall output. |
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01-09-2019, 10:34 AM | #36 |
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01-09-2019, 12:42 PM | #37 |
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Said it before, and I'll probably say it again (not picking on your). The only change is that it's no longer a correctable violation. The actually exhaust law has been in place since the late 50s and updated it 1998. So if you didn't get a ticket last year, you won't this year. Also, if it's that big of a deal, keep the stock exhaust and if you get a ticket, swap and get tested.
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01-09-2019, 05:28 PM | #38 |
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01-09-2019, 05:51 PM | #39 |
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We cant even ship LED bulbs to Germany anymore
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01-09-2019, 06:48 PM | #40 | |
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01-09-2019, 11:07 PM | #41 | |
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The new law isn't a fixit ticket anymore. Just a straight fine. |
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01-10-2019, 07:54 AM | #42 |
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The very little amount of air flowing from the demonstration will not be affected by a muffler, especially since the OEM muffler is straight through, and the stock mid pipe has two cats and a resonator in it. Did you not notice the rag being sucked in to one bank on our mid pipe? This is not possible with the stock exhaust since the banks don't mix until much further back when the exhaust gases have already slowed down.
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01-10-2019, 03:17 PM | #43 | |
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There have been people already pulled over and fined for a completely stock exhaust. Now that individual has to waste his time to go to court to prove his car is stock. Grew up in SoCal, I no longer tell people I am from there. That place has become embarrassing. Much bigger problems to deal with than loud exhausts. There are police units actively searching just for loud exhaust right now. Money maker. |
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01-10-2019, 04:42 PM | #44 | |
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