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Thanks for the link.

You're right - I'm amazed at how quiet the exhaust is at idle and under light load. I had a dixis on my M3 and it was very loud, one of the loudest on the market, and that was just the can.
 

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Discussion Starter #23
The exhaust tone is low at idle and low revs. It's a higher pitch at high revs.

Under light loads, it's amazingly quiet. I'd say it's only a few decibels louder than the stock exhaust & resonator. Frankly, this is the way I like it because we live at the top of a long hill. Going up a 3 mile hill at light throttle is absolutely terrible when the car drones.

With heavy throttle though, it's definitely louder, and the sound carries a LOT. You'll wake the neighborhood... several neighborhoods if you're at 8k. ;)
 

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Discussion Starter #25
The loudness is difficult to answer.

From the inside of the car:

At idle, it's a little louder and lower.
At low throttle, low revs, it's also just a little louder and lower.
At mid throttle, low revs, again it's a little louder, and lower.
At high throttle and high revs, it's definitely louder, though not nearly as loud as an Eisemann, even Sport.

From the outside, it's easily louder in mid to high throttle, by quite a bit.

I paid $2500, used, for the exhaust & h-pipe.
 

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The loudness is difficult to answer.

From the inside of the car:

At idle, it's a little louder and lower.
At low throttle, low revs, it's also just a little louder and lower.
At mid throttle, low revs, again it's a little louder, and lower.
At high throttle and high revs, it's definitely louder, though not nearly as loud as an Eisemann, even Sport.

From the outside, it's easily louder in mid to high throttle, by quite a bit.

I paid $2500, used, for the exhaust & h-pipe.
That's the bargain of the century.
 

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Discussion Starter #28

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Discussion Starter #29
OK, have to apologize in advance for this clip. It was taken in windy conditions (should have shielded microphone, or purchased a wind sock), and the camera tries to compensate.

Also, the car & exhaust was still cool. It's not quite a cold start, but close. Because of this, you get some of that rattle/cackle in the exhaust that you often hear in the S85 application.

The revving is low to mid throttle (since car is still relatively cold, I don't like really stepping on it). As you can hear, idle or near idle produces a very low tone that carries. Higher up the RPM's produces a high pitched sound. I'd love for it to produce as high of a pitch as a Carrera GT with straight pipes, but I kinda doubt that's possible with this application. :(

No 1080p this time, because the file is 282mb.

58.9mb 480p Version

Youtube:

http://www.youtube.com/watch?v=4Qn-q1uj9oQ
 

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Discussion Starter #30
Installed the Eisenmann Section 1 today.





Alas, they were about 1/2" too short to mate up to the Dixis exhaust. *sigh* It kinda figures. Nothing is ever easy, is it?

The shop grabbed some 2.5" stainless piping and took a grinder to it:



Edges were then polished up to make sure it was clean and smooth, of course, as to not impede exhaust flow (and to keep leaks from happening):



And, one for the other side:



Welded those two 1/2" pieces to the two Eisenmann section 1 pieces, and then it was an easy bolt up installation.

Even the band clamps went back on well:



All on:

 

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how does the sound compare to the eisenmann sport and race? where did you order the exhaust from?
 

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Discussion Starter #32
BMC filters installed today too:



Oh yeah... the dyno.

The dyno used is a newly calibrated Dyno Dynamics dual roller eddie current dyno. None of this inertia dyno stuff. Bleh. If you want "bragging rights" numbers, there's an internal conversion for DynoJet. LOL.

Fan is a huge 12,000 CFM model that is dyno controlled for speed.





Dyno was, of course, done with the hood down.

The car had AA software, the Dixis Exhaust, and the Evosport Pullies.

That served as the baseline dyno (a few were done, average pull used)

The car then was pulled off and the Eisenmann Section 1 installed. Back on the dyno, then a few pulls were done, average pull taken.

Then, the car was allowed to sit for about 20-25 minutes to cool down, then BNC filters installed. A few pulls were done, average pull taken.

Unfortunately, the RPM's don't match exactly. Instead of digging through the engine compartment, we just used the calculated numbers (go to a certain RPM on the tach, then set on computer). It's close enough though.



As you can see the Eisenmann Section 1 increased the torque from down low to about 3500rpm, then there is a slight loss for about 1000 rpm, then a gain to near redline.

The BMC filters gave a nice bump in torque down low, then near baseline at 4800rpm or so, and then a nice increase through to near redline.

So, both of these things seem to help, especially through the low and mid ranges.
 

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Discussion Starter #33
OK, for the sound numbers:

Measured using Radio Shack sound level meter (#33-2050).

dB meter using slow response (so I can read it), with A weighting.

Measurements taken from 6" from driver's head. Windows closed. Air fan on lowest setting.

Before (with AA software, the Dixis Exhaust, and the Evosport Pullies):

Idle: 60dB
2000RPM in neutral: 59 dB
3000RPM in neutral: 62 dB
2000RPM in 4th gear, flat surface: 65 dB
3000RPM in 4th gear, flat surface: 68 dB

After (with AA software, the Dixis Exhaust, and the Evosport Pullies, plus Eisenmann Section 1 and BMC filters):

Idle: 54dB
2000RPM in neutral: 58 dB
3000RPM in neutral: 65 dB
2000RPM in 4th gear, flat surface: 66 dB
3000RPM in 4th gear, flat surface: 70 dB

For reference:
1 dB: lowest perceptable increase in sound
3 dB: doubling of actual sound pressure
10 dB: doubling of perceived loudness

However, these numbers don't tell the entire story. Though the sound level during cruising didn't really change, when your foot is in it, the exhaust growl is noticably louder. I'd say there's probably a 3-4 dB difference when floored.

The biggest plus: STILL NO RESONANCE, even through the 2000-3500RPM range.

That is simply awesome. I'm talking real no resonance, not the Eisenmann Sport "no resonance", or the Eisenmann Race "oh-my-god-what-is-that-sound" resonance.
 

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GREAT INFORMATION AND PICTURES!!! THANKS!
BTW, does anybody know the reason for the h-pipe or the x-pipe? Why is it necessary for the dual system to merge? What would happen if you didn't merge the 2 pipes? Just curious?
 

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Discussion Starter #36
I think they might have gone H instead of X simply because of the difficulty of bending titanium. I'm not positive though. This being said, it seems to work ok.

In general, you want dual systems to merge for 2 reasons:

1. Increase torque (improves scavanging)
2. Smooth out the sound
 

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Wow, excellent job NobleM400.:applause:
It is a shame you haven't got an original dyno of the car as standard.
It would be extremely interesting to see the total increase of all your mods put together.
I didn't see the maximum bhp figure on the chart.
There is only the number for torque.
 

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Discussion Starter #38
Apparently, the printer needed new ink. The HP is on the left, but it's the same scale as the torque (so you can just read the right column). It's around 436hp to the wheels. Using a drivetrain weight of 80 lbs (typical front engine, RWD).

Oh yeah, pulls were done in 4th gear. Of course, 5th and 6th would show higher, but it's not necessary when I'm just looking to gauge the effectiveness of the mods.
 

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OK, for the sound numbers:

Measured using Radio Shack sound level meter (#33-2050).

dB meter using slow response (so I can read it), with A weighting.

Measurements taken from 6" from driver's head. Windows closed. Air fan on lowest setting.

Before (with AA software, the Dixis Exhaust, and the Evosport Pullies):

Idle: 60dB
2000RPM in neutral: 59 dB
3000RPM in neutral: 62 dB
2000RPM in 4th gear, flat surface: 65 dB
3000RPM in 4th gear, flat surface: 68 dB

After (with AA software, the Dixis Exhaust, and the Evosport Pullies, plus Eisenmann Section 1 and BMC filters):

Idle: 54dB
2000RPM in neutral: 58 dB
3000RPM in neutral: 65 dB
2000RPM in 4th gear, flat surface: 66 dB
3000RPM in 4th gear, flat surface: 70 dB

For reference:
1 dB: lowest perceptable increase in sound
3 dB: doubling of actual sound pressure
10 dB: doubling of perceived loudness

However, these numbers don't tell the entire story. Though the sound level during cruising didn't really change, when your foot is in it, the exhaust growl is noticably louder. I'd say there's probably a 3-4 dB difference when floored.

The biggest plus: STILL NO RESONANCE, even through the 2000-3500RPM range.

That is simply awesome. I'm talking real no resonance, not the Eisenmann Sport "no resonance", or the Eisenmann Race "oh-my-god-what-is-that-sound" resonance.
Thanks for the report.:applause:

I wonder how loud would it be at cold-start in the morning. Would you mind measure the dBA number using your magic meter from the Radio Shack? I'm myself love the sound/tone of Eisenmann Meisterschaft, but unfortunetly, I have to (unwilling to) put back the stock muffler. Currently, I got eisenmann section1&2 and still undecide what to put next for the muffler. Narrow down to two choices: Dinan and Meisterschaft Touring, but I guess Dixis would be a candidate after reading your report. How about the downshifting sound because with my stock, it has no "Boom" effect like my old eisenmann meisterschaft.

Hope you enjoy your setup :cheers:
 
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