Another Fister III Impression Thread
10-18-2014, 04:33 AM
#1
Rennlist Member
Thread Starter
Another Fister III Impression Thread
I had the Fister III installed on my 97 C2S (thanks to Mike J) and would like to share my impression with a slightly different opinion as the majority of the other Fister's owners.
I wait for two months and my Fister III exhaust finished with Cermachrome coating finally arrived last Friday. I can't wait to get it installed so I went to Mike J's garage the next day and the installation is very easy and straight forward. When I first started the engine the roar of the exhaust is just incredible it's just like the car has been reborn. Then I went for a drive and found that the exhaust did drone between 2.5k -3k RPM when I pushed on the gas pedal. When I lift off the gas pedal then the drone was gone. The sound is very sporty and alive once it passed 3k RPM. Inside the cabin it's actually not as loud as I originally thought (except the drone). When I opened the window there was less drone and more of the sweet exhaust noise. I know I have to change my driving habit a bit to avoid the 2.5 to 3K range.
Don't get me wrong, overall I still love the exhaust and Darin from FD Motorsport is a super nice and easy guy to work with. I am just surprised that after doing a couple hours of research here I only found one Fister III's owner which has similar impression. I had driven a friend's 993 C4S with Fister III before and found that it has the same drone at similar RPM. My friend called it "resonance" instead of "drone" although I don't really know what's the difference.
So my question is would it be something that my car (and my friend's one) was setup differently that cause the drone? For example one thing I know is that both our cars do not have the engine cover. Or is it just me who is more sensitive? I would like to see other Fister's owners opinion especially on the cabin noise between the 2.5k to 3k zone.
UPDATE: After about 300 miles the drone or resonance is almost completely gone, or it's progressively down to a level that it no longer bother me. It's just like magic. How could that happen?
I wait for two months and my Fister III exhaust finished with Cermachrome coating finally arrived last Friday. I can't wait to get it installed so I went to Mike J's garage the next day and the installation is very easy and straight forward. When I first started the engine the roar of the exhaust is just incredible it's just like the car has been reborn. Then I went for a drive and found that the exhaust did drone between 2.5k -3k RPM when I pushed on the gas pedal. When I lift off the gas pedal then the drone was gone. The sound is very sporty and alive once it passed 3k RPM. Inside the cabin it's actually not as loud as I originally thought (except the drone). When I opened the window there was less drone and more of the sweet exhaust noise. I know I have to change my driving habit a bit to avoid the 2.5 to 3K range.
Don't get me wrong, overall I still love the exhaust and Darin from FD Motorsport is a super nice and easy guy to work with. I am just surprised that after doing a couple hours of research here I only found one Fister III's owner which has similar impression. I had driven a friend's 993 C4S with Fister III before and found that it has the same drone at similar RPM. My friend called it "resonance" instead of "drone" although I don't really know what's the difference.
So my question is would it be something that my car (and my friend's one) was setup differently that cause the drone? For example one thing I know is that both our cars do not have the engine cover. Or is it just me who is more sensitive? I would like to see other Fister's owners opinion especially on the cabin noise between the 2.5k to 3k zone.
UPDATE: After about 300 miles the drone or resonance is almost completely gone, or it's progressively down to a level that it no longer bother me. It's just like magic. How could that happen?
Last edited by KP993; 11-01-2014 at 04:06 AM.
10-18-2014, 09:24 AM
#2
Rennlist Member
Absolutely zero drone/resonance/whatever in my car with Fister 3s.
I also have no engine cover, solid engine mounts, and semi solid transmission mounts. I've had quite a few droney exhausts, and consider myself pretty sensitive to drone. My Fisters were totally drone free.
I also have no engine cover, solid engine mounts, and semi solid transmission mounts. I've had quite a few droney exhausts, and consider myself pretty sensitive to drone. My Fisters were totally drone free.
10-18-2014, 10:04 AM
#3
Rennlist Member
no drone here either, no engine tray, no muffler heat shields, and Wevo engine mounts.
Never heard any Fister owner, l, ll's, or lll's complain of a drone at any RPM.
confused
Never heard any Fister owner, l, ll's, or lll's complain of a drone at any RPM.
confused
10-18-2014, 10:40 AM
#4
Rennlist Member
When I bought my car in 11' it had BB mufflers. Those things droned real bad and to me it felt like the exhaust was choked. There was a real weird booming sound in low rpm driving. Switched over the stage III's, the drone is gone and now has deep raspy growl. Power!!
10-18-2014, 11:27 AM
#5
MY 993 is THE DD and I love my F3s each and every day. No exceptions.
Ken
Ken
10-18-2014, 12:32 PM
#7
RL Community Team
Rennlist Member
Rennlist Member
I have never heard anyone complain about drone either. Have you contacted Darin to see if he can tweak them a little? FD has great customer service, I'm sure they will help you out if there is something they can do.
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10-18-2014, 02:32 PM
#8
Rennlist Member
this happened to me before I had fister III
the only time I had a drone was with a aftermarket air filter frame stock mufflers
went back to OEM filter frame installed III no issues hear!
I think the Magsilver finish made the difference :-)))
SC
the only time I had a drone was with a aftermarket air filter frame stock mufflers
went back to OEM filter frame installed III no issues hear!
I think the Magsilver finish made the difference :-)))
SC
10-18-2014, 02:59 PM
#9
In response to the original post:
You are right. there is some "drone" provided by Darin's cans albeit low enough in level to be of little consequence to most driver/listeners
Your friend is also right. It is a resonance. Every automobile cabin is a resonant cavity with a naturally occurring resonant frequency. A good analogy is the body of an acoustic guitar or any musical instrument. Musical instruments are designed and have evolved in a way in which the natural resonance of the instrument is altered in ways that compliment and enhance the sound of the instrument. Rooms possess the same qualities though we are less consciously aware of them. The fundamental frequency of the muffler in concert with the resonant frequency of the cabin and the RPM's (a frequency) of the engine can combine in a way which produces "drone", the emphasis of the resonant frequency of the cabin. 2.5-3k RPM seems to be the magic number in our case.
Darin's muffler has a naturally occurring, fundamental resonant frequency along with a complex of harmonics. The trick he performed, either by science or intuition, was to move the natural frequency of the muffler away from the resonant frequency of the cabin. In doing this, the cabin no longer reinforces or amplifies the muffler note. Because of the complexity of harmonics and the limited frequency range the muffler can operate in there will always be some overlap producing some "drone". Hearing it is a relative perception and in Darin's case his mufflers possess relatively less drone. For some it's enough less to qualify as "none". The muffler needs to be "tuned" to a frequency that gives us the degree of loudness we desire without the annoying resonant frequency enforcement. Of course the quieter the muffler is the less problematic the drone.
Being an audio professional, I have had it in mind, out of simple curiosity, to determine the resonant frequency of the 993 cabin. This was prompted by the irritating resonance (drone) of the Maxflo's my car came with. I now run Fister lll's. I would like to put a number on the frequency of the cabin but I've never gotten around to doing the test. It's not that complicated. You can do it with an iPhone app and a source of calibrated pink noise. The speaker system in your car could be good enough assuming it is reasonably linear. Otherwise a linear external speaker, small enough to fit inside the cabin would do. Low end is important. Pro gear is better but the iPhone app can get close enough. While its microphone isn't as linear as a calibration mic starting at about $700 or $800 it's been compensated for in the app software to be "good enough". The App (Audio Tools) is a RTA (real time analyzer) that gives you a graphic, 2D, representation of the real time frequency response of the cabin (or any environment). The pink noise source is inherently "flat". When played in the cabin, windows closed, through a flat speaker and measured with an RTA, the most obvious peak deviation from a flat looking response on the display indicates the resonant frequency of the cabin.
I've observed that under driving conditions the level of drone is affected by the load on the engine, not by just the three basic components of muffler, cabin, and RPM's. Aspects of suspension and materials properties come into play as well. This can become quite complicated.
Aside from satisfying idle curiosity, I have no idea what one would do with this information unless you were designing or manufacturing exhaust systems or automotive interiors.
richard beggs
You are right. there is some "drone" provided by Darin's cans albeit low enough in level to be of little consequence to most driver/listeners
Your friend is also right. It is a resonance. Every automobile cabin is a resonant cavity with a naturally occurring resonant frequency. A good analogy is the body of an acoustic guitar or any musical instrument. Musical instruments are designed and have evolved in a way in which the natural resonance of the instrument is altered in ways that compliment and enhance the sound of the instrument. Rooms possess the same qualities though we are less consciously aware of them. The fundamental frequency of the muffler in concert with the resonant frequency of the cabin and the RPM's (a frequency) of the engine can combine in a way which produces "drone", the emphasis of the resonant frequency of the cabin. 2.5-3k RPM seems to be the magic number in our case.
Darin's muffler has a naturally occurring, fundamental resonant frequency along with a complex of harmonics. The trick he performed, either by science or intuition, was to move the natural frequency of the muffler away from the resonant frequency of the cabin. In doing this, the cabin no longer reinforces or amplifies the muffler note. Because of the complexity of harmonics and the limited frequency range the muffler can operate in there will always be some overlap producing some "drone". Hearing it is a relative perception and in Darin's case his mufflers possess relatively less drone. For some it's enough less to qualify as "none". The muffler needs to be "tuned" to a frequency that gives us the degree of loudness we desire without the annoying resonant frequency enforcement. Of course the quieter the muffler is the less problematic the drone.
Being an audio professional, I have had it in mind, out of simple curiosity, to determine the resonant frequency of the 993 cabin. This was prompted by the irritating resonance (drone) of the Maxflo's my car came with. I now run Fister lll's. I would like to put a number on the frequency of the cabin but I've never gotten around to doing the test. It's not that complicated. You can do it with an iPhone app and a source of calibrated pink noise. The speaker system in your car could be good enough assuming it is reasonably linear. Otherwise a linear external speaker, small enough to fit inside the cabin would do. Low end is important. Pro gear is better but the iPhone app can get close enough. While its microphone isn't as linear as a calibration mic starting at about $700 or $800 it's been compensated for in the app software to be "good enough". The App (Audio Tools) is a RTA (real time analyzer) that gives you a graphic, 2D, representation of the real time frequency response of the cabin (or any environment). The pink noise source is inherently "flat". When played in the cabin, windows closed, through a flat speaker and measured with an RTA, the most obvious peak deviation from a flat looking response on the display indicates the resonant frequency of the cabin.
I've observed that under driving conditions the level of drone is affected by the load on the engine, not by just the three basic components of muffler, cabin, and RPM's. Aspects of suspension and materials properties come into play as well. This can become quite complicated.
Aside from satisfying idle curiosity, I have no idea what one would do with this information unless you were designing or manufacturing exhaust systems or automotive interiors.
richard beggs
10-18-2014, 07:08 PM
#10
Nordschleife Master
Ok I think I have your answer , I own 11 993's and 8 of them have fister III exhaust , the lower mile cars are a little louder than the higher miles , I think this happens because the catalayer converter on the low mile cars are cleaner than the high miles cars and that's why they are louder , regardless there's nothing but love here for the fister III's 
10-18-2014, 07:19 PM
#11
Rennlist Member
And there we have it! Thanks for the technical explanation and write-up.
I previously had Fabspeed Supercups, and the drone (combined with low pitch and volume) were just too much for my ears. I started to notice some tinnitus on the days I drove the car - maybe I'm sensitive, but they had to go.
Would like to hear the III's someday - my stock motorsound option setup is way too quiet.
Besides the better sound, I actually find rev matching easier when I can better hear the engine.
Cheers
Matt
I previously had Fabspeed Supercups, and the drone (combined with low pitch and volume) were just too much for my ears. I started to notice some tinnitus on the days I drove the car - maybe I'm sensitive, but they had to go.
Would like to hear the III's someday - my stock motorsound option setup is way too quiet.
Besides the better sound, I actually find rev matching easier when I can better hear the engine.
Cheers
Matt
10-18-2014, 11:10 PM
#13
Burning Brakes
I have drone in my 2014 grand cherokee srt8 with stock exhaust!!!!!!!!
No drone in my 993 with fister III !
No drone in my 993 with fister III !
10-19-2014, 12:16 AM
#15
Rennlist Member
Ok I think I have your answer , I own 11 993's and 8 of them have fister III exhaust , the lower mile cars are a little louder than the higher miles , I think this happens because the catalayer converter on the low mile cars are cleaner than the high miles cars and that's why they are louder , regardless there's nothing but love here for the fister III's
Maybe it's time for an Italian tune up!
Where's Leon these days anyway?
The mufflers will change a little over time as particulate builds. Give them about 1,500 miles and any tinniness goes away.
Everyone who hears my II's says they sound awesome.
Regards,
.
Regards,