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YOUR RESEARCHBy pass pipes?
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Install resonators
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I like how you installed the resonators because you still have space/length available to install Car Chemistry or similar baffles to tweak the exhaust sound and resonance .
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Suggestion · Original poster
My 01 996 C4 is running stock exhaust and looking into something that sounds better (louder).
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Suggestion · Original poster
Ordered a set from eBay and hoping to have them here by Friday.
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Install resonators
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I like how you installed the resonators because you still have space/length available to install Car Chemistry or similar baffles to tweak the exhaust sound and resonance .
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I did it, bypass by themselves were really loud and hated the drone, I then installed a triple baffle to the bypass pipes and it took away the drone and still not as bad, very happy with the Fister mufflers.
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My 01 996 C4 is running stock exhaust and looking into something that sounds better (louder). I noticed some folks talking about "by pass" pipes? Could some explain them to me? I understand "by pass" the muffler, but are they hard to install? Anyone running them? Thoughts? I don't care about drone just looking for something more aggressive sounding without going to a full exhaust.
Look up "Gundo hack"/ Inexpensive and still gives you quiet when you drive easy on it IMO, Love mine and I didn't have to spend a fortune for now. When the mufflers or Cats give out, then I'll look into a real performance system.
+1! I did this on my car and love it.
If Gundo (or Fister) is a 5 on the loudness scale of 1-10 (1 being stock), then a complete bypass is likely to be at least a 7 if not more. No denying the weight loss, though, the stock cans are heavy. Do a lithium battery and you�ve saved possibly 80lbs. But for me, too loud.
I did it, bypass by themselves were really loud and hated the drone, I then installed a triple baffle to the bypass pipes and it took away the drone and still not as bad, very happy with the Fister mufflers.
Ordered a set from eBay and hoping to have them here by Friday. Will post before / after sound clip. "Drone" doesn't bother me although I don't drive the car for 2 hours straight......yet :P).
I've looked into the bypass pipes a few times over the years for my 996 and I always came to the same conclusion - they are WAY too loud! I always planned on going the Fister muffler route but I don't drive this car much anymore so I never got around to making the switch. Interested to hear your thoughts on the bypass pipes Viper...
My 991.1 C2S has full SOUL headers (200 cell cats) and valved exhaust so I kind of like the "loud" tone to be honest but yes I will advise my thoughts. Best thing about it is they only cost $110 shipped so if I don't like them I can take them off and put the mufflers back on....so it's not like I'm out $1000's of dollars.
The cats act as pretty good mufflers. The difference between bypass with and without cats is the difference between feeling OK driving it on the road and knowing if I passed a cop I was getting pulled over.
I had the FabSpeed muffler delete and just went back to stock yesterday. So much happier. To answer the OP yes the mufflers are removed in the bypass. It goes headers, cats, then ehxaust tips. No mufflers. Damn that thing was loud. Sounded amazing on start up, taking off from stop lights and stomping the throttle. At cruising speeds sounded like someone put the back window of a sedan down. Just this annoying drone vibrating sound that made casual conversation and listening to anything on the radio difficult. I also could never drive it to work with small kids in the house and neighbors I am very friendly with or else everyone gets woken up when I leave for work at 5:50am. Even the guys at Fab Speed said they don�t drive with muffler deletes. I don�t track mine.
I wanted the weight reduction gained by the bypass pipes/ muffler deletes (most have it listed as a 40# drop all the way in the back), however I knew that I was going to hate the noise, so I searched for a solution that would be the best of both worlds. I was leaning towards more weight reduction in exchange for more noise. This is my solution and my buddy is ready to make more if your deletes are too loud... I’m still a few weeks away from finally installing them but will offer a comparison with my gundo-hacked OEM mufflers.
Should net a 33-34# weight loss still
@2mAn
I actually also incorporated some smaller total flows into muffler deletes/X pipe with 200 cell cats and headers when I had my 996.1 car.
It sounded fantastic and definitely helped cut some of the annoying drone around 2,600-3,000 range. If anyone wants some sound clips to get an idea, the auto broker I sold this car to has the sound clips linked on the old BAT listing (included below)
Hope it’s helpful to get an idea of what to expect with the combo.
https://bringatrailer.com/listing/20...11-carrera-99/
Excellent sound !! I really like the higher pitched Timbre !! Is this exactly the same as 2mAn is making? if so I need a set for my sons 99 Cab it has Fabspeed headers and X pipe with by-pass pipes and my Son says is too loud for the street....
This is what I added to the bypass pipes, use 2 1/4 inch 3 baffles unit, took away all the drone. but for long drives and any conversation was hard in the Cabriolet, no experience in coupe with this set up. being in the west coast the top is down most of the time.
Exhaust - CC Inserts - Page 1 - Car Chemistry, Inc.
Wow, this looks like a great idea. How do you plan to connect these to the exhaust system?
I wonder if those TotalFlow mini mufflers will provide enough back pressure (more so than the standard bypass pipes) to minimize, or even eliminate, the loss of low-end torque that occurs with a muffler delete system?
^^^HAHA^^^
Well, maybe I simply don't know any better.
However, IIRC, I remember seeing dyno runs that showed loss of low-end torque for various cars with muffler delete setups - the 996 M96 included in this group. Not to mention many butt dyno reports of loss of low-end torque...and unlike real dynos, butt dyno results are NEVER wrong.
Me and
@2mAn
have been on the same journey (98 c2 lightweight)�.after getting a carbon ducktail,�I worked on the exhaust. X pipe with total flow cheap resonators sound amazing, high pitched, and exotic.
Thanks,
@Porschetech3
I actually used a slightly smaller resonator. If I were ever to do it again, I’d use the slightly larger sized total flow resonator
@2mAn
used, just to get even more drone compliance. My 996.1’s sound was everything I was looking for with this combo!
link for the resonators used
https://www.totalflowusa.com/totalfl...id-225-inch-od
Matthew Tanner is your x-pipe catted or catless ? I like how you installed the resonators because you still have space/length available to install Car Chemistry or similar baffles to tweak the exhaust sound and resonance . Looking forward to some audio clips .
Yes, my Sons 99 Cab has the Car Chemistry 3 baffle units ( and I even installed some "glass packing" in the baffles) but he says it's still too loud with the Fabspeed Headers and Fabspeed X-pipe.....so maybe these Total Flow resonators are the ticket...
I also recommend getting the Gundo Hack done. i was lucky enough to find someone selling a set of gundo'd mufflers so i bought them for $300. They sound really good good. theyre basically a sport exhaust with the flap always open. and cheap, but sound great.
I had a local fabrication shop install a "Fisher" bypass between the muffler inlets and outlets. Just putting around town it is pretty mellow sounding, but livens right up once you are over 3500 rpm. I can't remember the cost, but it was pretty reasonable. I did the muffler R&R which went pretty well after a couple of days of Kroil soaking. The hardware was even serviceable afterwards.
Doug
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