DIY: 991 Exhaust Sound Mod
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Joined: Aug 2015
Posts: 27
From: south
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Joined: Jul 2016
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I might try this mod out and see. Any lost of MPG with this mod?
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Joined: Sep 2013
Posts: 143
From: northern nj
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just meant that I wish I had done PSE sooner instead of messing around with the mod. It's definitely a noise maker but I can "feel" more horsepower haha.
I didn't notice any substantial decrease in MPG. I do now actually have a decrease because I'm revving it much much higher to hear the exhaust note.
I didn't notice any substantial decrease in MPG. I do now actually have a decrease because I'm revving it much much higher to hear the exhaust note.
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Joined: Jul 2016
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just meant that I wish I had done PSE sooner instead of messing around with the mod. It's definitely a noise maker but I can "feel" more horsepower haha.
I didn't notice any substantial decrease in MPG. I do now actually have a decrease because I'm revving it much much higher to hear the exhaust note.
I didn't notice any substantial decrease in MPG. I do now actually have a decrease because I'm revving it much much higher to hear the exhaust note.
lol.. i hear ya about the rev. I put them in Sport/plus sometimes just for fun driving at 25 mph traffic.
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Joined: Oct 2016
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From: western ma
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tried this mod and loved it. I have a cab so with the top down you really get to enjoy the sound. I want to make it switchable so in the spring I'm going to install a normally open vacuum solinoid in line and run a wire to the cabin with a switch so I can switch it back and forth
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Joined: Feb 2012
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From: MN
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Wow, I tried this on my 2013 S Cab without PSE, and hated the new sound. It sounds horrible just a loud muffled sound with no character. Maybe some cars sound different. I drove a few miles and went straight back to the garage to reverse it. BTW I was able to reach the T connector from the top passenger side after removing the fans. I put a rubber stopper over the vacuum Port and wrapped some vinyl tape over the connector that I removed. But like I said, it wasn't that way for long.
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tried this mod and loved it. I have a cab so with the top down you really get to enjoy the sound. I want to make it switchable so in the spring I'm going to install a normally open vacuum solinoid in line and run a wire to the cabin with a switch so I can switch it back and forth
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Joined: Oct 2011
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From: West Palm Beach, FL
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Well I’ve added catless headers as well now. It sounds wicked. There’s a little drone nothing too bad. With just the valves always open before the headers I didn’t have drone. I also ended up with a pro Cobb tune which eliminated any warnings.
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Joined: Nov 2018
Posts: 9
From: Arizona
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I am seriously thinking about doing this mod as I love the way my C4S sounds with the valves open (non-PSE exhaust). My shop says they have done a few of these. Said they have done the same thing to Ferrari 458's. Wondering if anyone has a video of what this mod sounds like... thanks