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      04-22-2012, 09:45 PM   #1
Finnegan
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Drives: Z4M/. Z3M, E36/46 M3
Join Date: Oct 2008
Location: Teaching the dog to slalom

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Exhaust Option Comparison

Video and the Data Sheet for the Exhaust Comparison can be found below. We recommend a good sub-woofer and sound system for full range and effect!

Overview: On 4/21/12 at Exhaust 'Fest, we completed a comparison of many exhaust and intake options. The goal was to use the same equipment, same approach, and same measurement techniques (see caveats). Results are still draft at this point as participants are still proofing the document. Once it's final the final document will be uploaded it into this post.

Caveats: We are not scientists; we were a chatty bunch; there were planes overhead; each driver revved their car slightly differently; the sun was in our eyes...you get the idea. All things said though the equipment was the same for each test, so this is about as good as it gets without bringing in guys with lab coats.

Conditions: 80 - 85 degrees F. Sea level.

Sound Measurement: Radio Shack Sound Level Meter, cat. no 33.2055. Response was set to "fast" and weighting was set to "c".

Video Equipment: Canon 7D, 1080p 24fps, Azden SMX-10 mic, 5 ft tripod

Parked Testing Method: For parked rev testing, we were 10 feet behind each car and both the camera and the dB meter were angled off to the driver's side (not directly behind the car). dB meter was pointed at the car, while holding it horizontally to the level of the pavement. Cars were revved to 5K RPM 3 times. An average db was taken as well as a max dB. Exhausts that "popped" when the throttle was released showed a spike in dB. That is noted in the data sheet.

Drive by Testing Method: For drive by testing we were about 20 feet away from the car as it went directly by. The meter was panned along with the video camera as cars drove by.

Participants: Beta, Dorifto88, Mfanatic325, RobMCoupe, jdl1pt, Marinb, gferil, AestheticStorm, e for effort, Skelekitty, Runner X, Finnegan, flpnout, MrZ07.

Special Thanks: GFeril for organizing this event and taking dB measurements, AestheticStorm for camera duty, and flpnout for hours of editing magic, and to all the Zpost members who participated and helped out!





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Last edited by Finnegan; 10-14-2013 at 01:06 AM..
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