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YOUR RESEARCH996 muffler bypass
Leading reported evidence
Install after the cats and o2 sensor
Performed · outcome unconfirmed
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Performed · outcome unconfirmed
also, no CEL, its installed after the cats and o2 sensor
Leading evidence: 'Install after the cats and o2 sensor' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Install after the cats and o2 sensor' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed
The car had the bypass installed prior to me owning it.
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Performed · outcome unconfirmed
The original owner had Mille Miglia stainless mufflers fitted then replaced them with a set of OEM mufflers because he didn't like the loudness of the Mille Migs.
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Great on my track car and I use the stock Cats for muffler and a bit of back pressure.
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Performed · outcome unconfirmed
The original owner had Mille Miglia stainless mufflers fitted then replaced them with a set of OEM mufflers because he didn't like the loudness of the Mille Migs.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
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Suggestion
back in the day, 356's came with roller bearing mains -those failed at about the 30k mark are almost ALL have been "upgraded" however there are still a few running around
Use shells v-power 91 only and have had no problems
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Suggestion
I bought the car with the bypass already done but I believe it was the Fabspeed muffler bypass, no issues at all, only time iv had CEL come up is when I switched from 91shell to 94 petro (o2 sensor), now I just use Shells v-power 91 only and have had no problems
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39 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
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guys what problems should i expect in installing the muffler bypass pipes? i'm looking for cel info, reflash? things along that line. i'm sure there is a constant drone,but how bad? thanks, scott
It is a pretty straight forward install for a muffler bypass. Just remove old mufflers and place the bypass there. If you get a cel, you could just clear the codes away. Droning is pretty bad ...
Cheers
If you want to hear sorta what it sounds like just remove your cats and fire it up. A novelty, but I don't think you would want to drive it around like that for long.
As for the CEL, you can install O2 simulators.
I have them on my car right now and they are obnoxiously loud. They make the car sound super pissed off and really mean, but the noise inside the car is louder than the noise outside the car to the point of being headache inducing.
I put them on my car Saturday and by Sunday afternoon I was picking up a Fabspeed setup to replace them.
I'll still hold onto them for track days though because you can really feel the 50 pounds missing from the rear of the car.
I have had mine for 2 years and I still love the sound every time I drive it. While it is not a daily driver, I do drive it every weekend and the sound does not drone. We are not driving Cadillacs...
I'm def with you on this one. The car had the bypass installed prior to me owning it. I drive it about every day it does NOT rain... I'm rarely low enough in the rpm's to call it droning
Turn the music up
I had fun driving with them.
Other performance drivers would pull up and give mad props!
Really does give Cup Car sound but pretty obnoxious in local traffic lol.
Had them on the car for a while. Worst decision I ever made.
Fine for a track only car, but not appropriate for the street.
You won't have any codes since you will not be touching the cats. Just the mufflers.
I'd really love to hear these things in person because they sound great in every video I've seen online. FWIW, if you're considering alternatives, I've got EvoMS headers and a Fabspeed exhaust on my C4S. They sound great...especially with the top down. I can't wait for the Spring!
-Eric
I got a bypass on my 99 Carrera... I could never go back to a stock sound, the motor just screams down the road, people hear you many blocks away, some will complain and yell at you to slow down even going the speed limit which always puts a smile on my face( 99% of the time angry 80+ year olds), alot will give you the thumbs up, Iv gotten 2 "Improper muffler" tickets for 110$ each within a year of daily driving (live in Canada, Ontario). when it comes down to it, I wouldn't go back to stock if I got a ticket every week
1999 Porsche 911 carrera (996) 3.4L muffler bypass revving sound - YouTube
- here's a video of mine
I've been on the fence about replacing my PSE in favor of this (for weight reasons) but damn, that sounds
real
good! What brand/make bypass are you using? Any CEL issues whatsoever?
I bought the car with the bypass already done but I believe it was the Fabspeed muffler bypass, no issues at all, only time iv had CEL come up is when I switched from 91shell to 94 petro (o2 sensor), now I just use Shells v-power 91 only and have had no problems
I thought about installing the muffler bypass as well. What I did was unbolt the clamps before the muffler and separated the pipe about an inch on each side and drove around a couple days. It was cool at first an brought a lot of attention, but I use mine as a daily driver and it was too much noise. Ill just use my 68 Camaro with a straight piped 454 for when I feel like being noisy
just finished my install last night and one word, Awesome!!
I will agree , they are loud but not as bad as some of the motorbikes i have heard(harleys).
I have a cabriolet and i love hearing the sporty sound when i accelerate.
I live in a very quiet, well used to be quiet,lol, neighborhood and none of my neighbours say that its bad enough to **** them off.
also, no CEL, its installed after the cats and o2 sensor
Plus 3 for me. Had them for 2 years. Sound great to me and not that difficult to watch the gas pedal with them early in the morning. I drive by cops all the time who do not notice. When you really hit it.....that is a different story.
BTW, never had a check engine light because of them and they were a used no name brand I got for $75.
I have no droning issues either, theres a sweet spot on the pedal that basically makes it sound stock when your cruising, although I always keep mine screaming down the road..... til I see a cop, then its "sweet spot" time
Fortunately, my car came with two muffler sets. The original owner had Mille Miglia stainless mufflers fitted then replaced them with a set of OEM mufflers because he didn't like the loudness of the Mille Migs. Guess what I did when I got the car home? After fitting the Mille Migs, I can say that my car sounds just like a Porsche should. My neighbours can hear me coming from two blocks away.
The best noise is backing off from around 6000 rpm... A beautiful noise. The motor spins quickly to the red line too. I would say they can be a bit drony if you select too high a gear.
BLAH
Sorry, but by-pass pipes on M96's sound horrid - esp at low rpm...the tone is wrong, the volume is wrong and the weight savings is right ---- so unless you need to shed a few pounds avoid these things - if you think they sound good, have a friend drive your car and you follow it
if you still think they sound good, see a Dr
still has the unique Porsche gurgle... you just get more of the raw motor sound, and you shouldn't be driving a Porsche at low rpm anyways, maybe your the one that needs to see the doctor?
hahahhaha
OK - pop quiz - who know the reason Porsche owners have it in their head that high RPM's are better
(BTW - I see redline everyday, many times - I dont have any problem driving on the freeway in 3rd --- hell I dont even own a 6th gear)
no takers on the pop quiz - heres some vintage Porsche trivia for ya
back in the day, 356's came with roller bearing mains -those failed at about the 30k mark are almost ALL have been "upgraded" however there are still a few running around
the story goes that if you kept the rpms "UP" the bearing would not fail (as fast) - something about oil pressure and keeping the bearings rolling - and there is plenty of documented evidence that keeping the rev's UP actually worked (in this application)
so "legacy" tribal knowledge is why you've heard "keep the rpm's up on your Porsche"
OK - back to your regularly planned boring azz Tuesday morning
I thought about bypass pipes, but then I found Fister D mufflers. Had them on since Christmas, they sound Fan Effing Tastic. From about 5K on they are "ON THE PIPE" and really sound great. If you are just putting around town no one notices. Love them.
Kone Killer
I have had the Fabspeed muffler bypass pipes on for the last two weeks and i still think its amazing!
I also installed the Fabspeed competition intake and the two make a great pair.
I ran it with the stock air intake and the fabspeed actually sounds less harsh, gives it a better, smoother sound in my opinion.
I also want to add, most people put on the pipes, start the car and rev the @#$% out of it,,, i let it warm up, then give it a quick "blip" of the throttle and you will hear the engine calm down considerably. I live in a very quiet area and i take off down my street fairly slow, no more than 3500 rpm and its fine, when you punch it, you will be smiling from ear to ear.
+1 for Fister Ds. Great sound when you want it. Fairly stock at cruising speeds.
FD Motorsports are also great to work with. Their fabrication is outstanding. Unless you are doing a full system replacement, this is the solution!
Gundo hack done like fister mod with pipe connecting inlet to outlet pipes sounds amazing. No drone! Only hear a deep throaty sound when you mash the gas.
highly recommended!
I have the deleted on my daily driver. Before installing them, I bought a set of baffles that I modified to fit. The sound is great and I have no noticeable drone. I leave for work at 05:30a.m. and when asking the neighbors, no one hears me.
