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Swift Racing Technologies · 08-27-2012, 10:54 AM

Hi Everyone,
Ok, so we have some mixed reports on the drone with the exhaust system.

I am not 100% sure why some people are reporting drone while others say that they have no drone. Our test car had no drone as well, as you saw in the videos. I will be the first to tell you that I cannot stand any exhaust systems that have even the slightest drone inside the cabin, perhaps it is my old age, or perhaps I simply like to have the ability to relax and drive while having a conversation with someone inside the car or over the phone. We went through 7 different muffler/resonator combinations over a 3 week period and selected this combo because in our test car it caused no drone and the tone was not obnoxious or too loud (I will tell you this it is a little loud only during cold starts for the first 30-45 seconds then it goes almost silent at idle, that is due to how the factory does the overlapping of the valves during cold starts for quicker warmups).

The center resonator we used is densely packed round resonator with the following dimensions: 4" diameter, 12" long actual body length, 17.5" overall length. We had a couple of people asking for a louder system and got the smaller center resonator with it being 4" round and 6" actual body length and 11.5" overall length. Ironically they have not complained about it being too loud or droning.

We may have another option. We have a 5" diameter, 12" long body length, 17.5" overall length resonator that we may be able to switch the center resonator out with. I said "may" because we have to make sure that there is adequate clearances for the bigger diameter. If we can fit that resonator in there I can pretty much guarantee that there will be absolutely no drone in the car for even the discriminating individuals. We did tests on another platform and the reduction in lower/cruising rpm drone between the two resonators was night and day.

Let me know what all of you think and we can make this happen and tone it further down for those of you that are getting "old" like myself, lol.

08-27-2012, 10:54 AM	#649
Swift Racing Technologies Join Date: Jun 2012 Drives: 2013 Scion FR-S Location: Boostville, MD Posts: 149 Thanks: 126 Thanked 321 Times in 78 Posts Mentioned: 2 Post(s) Tagged: 0 Thread(s)	Hi Everyone, Ok, so we have some mixed reports on the drone with the exhaust system. I am not 100% sure why some people are reporting drone while others say that they have no drone. Our test car had no drone as well, as you saw in the videos. I will be the first to tell you that I cannot stand any exhaust systems that have even the slightest drone inside the cabin, perhaps it is my old age, or perhaps I simply like to have the ability to relax and drive while having a conversation with someone inside the car or over the phone. We went through 7 different muffler/resonator combinations over a 3 week period and selected this combo because in our test car it caused no drone and the tone was not obnoxious or too loud (I will tell you this it is a little loud only during cold starts for the first 30-45 seconds then it goes almost silent at idle, that is due to how the factory does the overlapping of the valves during cold starts for quicker warmups). The center resonator we used is densely packed round resonator with the following dimensions: 4" diameter, 12" long actual body length, 17.5" overall length. We had a couple of people asking for a louder system and got the smaller center resonator with it being 4" round and 6" actual body length and 11.5" overall length. Ironically they have not complained about it being too loud or droning. We may have another option. We have a 5" diameter, 12" long body length, 17.5" overall length resonator that we may be able to switch the center resonator out with. I said "may" because we have to make sure that there is adequate clearances for the bigger diameter. If we can fit that resonator in there I can pretty much guarantee that there will be absolutely no drone in the car for even the discriminating individuals. We did tests on another platform and the reduction in lower/cruising rpm drone between the two resonators was night and day. Let me know what all of you think and we can make this happen and tone it further down for those of you that are getting "old" like myself, lol.