c5 mid muffler
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2nd Gear
Joined: Sep 2018
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c5 mid muffler
Hello, i have a 1998 a4 , with a billy boat exhaust system on the back, but it does not have the real loudness i'm looking for. Would removing the cats put any back pressure or anything on my engine? I spoke to a shop who said they would do it and bypass the 02 sensors for 200 dollars. what else would happen other then making it louder? has anyone done anything like this with the mid mufflers and enjoyed the sound it was compared to before.
MS , so straight piping even a v6 mustang is totally legal.
MS , so straight piping even a v6 mustang is totally legal.
Last edited by BradyBatia; Dec 11, 2018 at 01:35 PM.
Team Owner
Joined: Mar 2001
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From: small town in S.E Pa. PA
St. Jude Donor '03-'04
There is no such thing as mid mufflers on a C5 mid mufflers are also called resonators, however the C5 does not have them, they do have catalytic converters which are illegal to remove.. The 02 sensors are part of the closed loop computer system. I would avoid a shop who would offer to do this and not tell you the implications of this action. If you want a more aggressive exhaust tone, buy a more aggressive exhaust system.
Last edited by Vetteman Jack; Dec 10, 2018 at 09:14 PM.
Team Owner
Joined: Dec 1999
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
The only mufflers are at the rear of the car and are typically located to the outside of the exhaust tips. The two catalytic converters are up near the clutch. You could talk to a shop about removing the two cats and the O2 sensors but that would require modifying the ECM programming to delete the O2 sensors.
You didn't say where you live but many states still require emissions testing and removing the cat can result in a test failure. Especially a visual inspection. And many shops wil not cut out cat as it's a violation of federal emissions laws and can result in a 5-figure fine to the shop that gets caught.
You might just try removing Billy Boat mufflers and replacing them with tubing. That should give you more exhaust noise!
You didn't say where you live but many states still require emissions testing and removing the cat can result in a test failure. Especially a visual inspection. And many shops wil not cut out cat as it's a violation of federal emissions laws and can result in a 5-figure fine to the shop that gets caught.
You might just try removing Billy Boat mufflers and replacing them with tubing. That should give you more exhaust noise!
Safety Car
Joined: Jul 2010
Posts: 4,013
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From: Chandler AZ
Hello, i have a 1998 a4 , with a billy boat exhaust system on the back, but it does not have the real loudness i'm looking for. Would removing the mid mufflers put any back pressure or anything on my engine? I spoke to a shop who said they would do it and bypass the 02 sensors for 200 dollars. what else would happen other then making it louder? has anyone done anything like this with the mid mufflers and enjoyed the sound it was compared to before.
The flange of the muffler that bolts to the catalytic converter has broken at the weld, so I took off both mufflers.
The plan was to take the one side and get it rewelded and reinstall ASAP, but at the time I liked the loudness of it, drove it like that a while, until finding C5 factory mufflers with factory chrome tips, my factory mufflers didn't have those, Craigslist for 100 bucks, bought 2 new muffler to flange gaskets at a GM dealer for about half of what I payed for my used mufflers, and put new used mufflers on.
Without mufflers the exhaust sounded loud but with a higher pitch tone, and it popped like a old pickup with glass packs sometimes or backfired.
At first I thought the car was faster, but I think it was in my head.
Also driving slow (5 mph or less, such as driving in front over a grocery store going slow as people are going in and out of store) I could hear what I think was exhaust going backwards.
Putting the new used mufflers on it sounded quite and the good deep tone was back and no more popping or weird noises.
Having no mufflers might make the tone sound crappy, and you may even lose performance.
I could feel the car had more get up and go after putting on the mufflers, just a little bit though.
Last edited by 1999corvettels1; Dec 10, 2018 at 06:37 PM.
