15 captured repliesPartial discussion capture · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHmuffler bypass vs MOT
Reported or suspected cause
engine temperature
Suggestion or failed attempt
No successful repair reported for this finding.
0
Identified cause
1
Suspected cause
0
Reported fixes
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that suspect a cause
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suspected cause
I've run bypass pipes before and the first 996 wasn't an issue on the MOT emissions whereas the current one took a while to claw its way through on the CO readings - I suspect the engine temperature on my car for the latest test wasn't quite as hot as it could have been which wouldn't have helped.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I have £20 mod done at local exhaust repair shop, it is not as loud on start up and if driving slow you can live with it but under load noise is insane in good and bad way depends on your day I guess :lol:
Leading evidence: 'engine temperature' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'engine temperature' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Repair shop' (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.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that suspect a cause
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suspected cause
Passed the next MoT so I'm not sure if it was the join or his probe was playing up.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I have £20 mod done at local exhaust repair shop, it is not as loud on start up and if driving slow you can live with it but under load noise is insane in good and bad way depends on your day I guess :lol:
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
You will lose power as I can feel it so if you would like to do it more correct you should make it longer I think every repair shop should do it for you as it will be very easy job.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I've run bypass pipes before and the first 996 wasn't an issue on the MOT emissions whereas the current one took a while to claw its way through on the CO readings - I suspect the engine temperature on my car for the latest test wasn't quite as hot as it could have been which wouldn't have helped.
These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.
Repair shop
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I have £20 mod done at local exhaust repair shop, it is not as loud on start up and if driving slow you can live with it but under load noise is insane in good and bad way depends on your day I guess :lol:
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
You will lose power as I can feel it so if you would like to do it more correct you should make it longer I think every repair shop should do it for you as it will be very easy job.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I've run bypass pipes before and the first 996 wasn't an issue on the MOT emissions whereas the current one took a while to claw its way through on the CO readings - I suspect the engine temperature on my car for the latest test wasn't quite as hot as it could have been which wouldn't have helped.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I've run bypass pipes before and the first 996 wasn't an issue on the MOT emissions whereas the current one took a while to claw its way through on the CO readings - I suspect the engine temperature on my car for the latest test wasn't quite as hot as it could have been which wouldn't have helped.
These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.
engine temperature
No successful repair reported for this finding.
0
Identified cause
1
Suspected cause
0
Reported fixes
Read evidence and context
Discussions that suspect a cause
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suspected cause
I've run bypass pipes before and the first 996 wasn't an issue on the MOT emissions whereas the current one took a while to claw its way through on the CO readings - I suspect the engine temperature on my car for the latest test wasn't quite as hot as it could have been which wouldn't have helped.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
15 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
911uk: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261026T113718Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Hi folks,
as i have to change my mufflers anyway (mine are rotting and making all kinds of rattly sounds) i'm considering either a Topgear exhaust OR just a porscheshop and/or fabspeed straight pipes out of cats. Anyone running a straight piped 996 in the UK? I've seen videos on youtube of folks from US and australia, but want to hear from someone here.
- noise - how's that gonna go down at MOT? i don't see a dB limit anywhere just "excessive noise" - sounds like the tester will have free hand there
- emissions - are they affected bymufflers? I'd guess no, but I don't really know?
I think back boxes may affect emissions. (Although I can't understand how)
A couple of years ago my 997 failed emissions on one side, the tester stuck the probe in the other side and passed it, told me he thought it was due to gases escaping either through the seam in the back box, or the join with the centre section.
I had the back boxes off for gundo, and couldn't see anything on inspection.
Passed the next MoT so I'm not sure if it was the join or his probe was playing up.
Straight through pipes would fail on noise I imagine, so you'll have to accept the chore of an annual pre-MoT swap.
Personally I would go with top gear. Straight through is obnoxiously loud in my opinion.
James
I've run bypass pipes before and the first 996 wasn't an issue on the MOT emissions whereas the current one took a while to claw its way through on the CO readings - I suspect the engine temperature on my car for the latest test wasn't quite as hot as it could have been which wouldn't have helped. I've just fitted Topgear boxes and 200 cell cats (the bypass pipes will be sold). My bypass pipes werent that popular in the village I live in for non petrolhead neighbours as they make a considerable noise on cold start-up BTW, though mine is used as an occasional 2nd car.
I had a painfully loud exhaust on a Nissan 350z I had once. I measured it at 106db inside the cabin. On its MOT the tester just made an advisory that the exhaust was loud and passed it.
My Ducati 996 has a similar advisory sometimes with its open race pipes.
So based on that I dont think noise is something they can fail on, and it will be fine as long as the car passes the emissions test.
ive run straight out from Cat in mine before (had a loop to mimic the route through the back boxes though).
Measured 105dB outside at track testing distance/conditions.
On the road it sounds awesome with pops/bangs/crackles etc, but it was robbed of some low down torque which was noticeable. Ended up asking Top Gear or one of them to make me an After Hours style exhaust which gave me back the torque and some pops.
Hi,
I have £20 mod done at local exhaust repair shop, it is not as loud on start up and if driving slow you can live with it but under load noise is insane in good and bad way depends on your day I guess :lol:
BAD:
M62 J21 to J22 (uphill) 6th 70-80 MPH on top of the motorway your ears screaming why are you doing this to us :floor: you can do it on 4th bit better but economy :eh!:
GOOD
Manchester night out all people screaming for rev, also on A roads experience is x2 with high revving as noise is so close to F1 mixed with V8 :thumbs: and on motorways I use rev as a honk so far works 100% every time :mrgreen:
So my kit is 2x 90 degrees pipes, unfortunately back tips will be with different angle but still looking nice forgot to take picture but:
You will lose power as I can feel it so if you would like to do it more correct you should make it longer I think every repair shop should do it for you as it will be very easy job.
Some pictures:
I've made up my mind, I'm doing it.
I found those and the price seems about right (unlike the £500 fabspeed nonsense)
https://www.porscheshop.co.uk/porsc...t3-silencer-by-pass-tail-pipes-1998-2002.html
Any coupons for porscheshop off this forum?
OMG £ 148......... I will take your boxes out and install mine pipes in this price this Friday......
I can give away my pipes as I'm back in muffler sound
uh:
PM if interested.
This is a source reference. Confirm exact model applicability in the original material.
