GT4 / Spyder Particulate Filter (Workaround)

GT4 / Spyder Particulate Filter (Workaround)

Author
Discussion

oo7ml

Original Poster:

191 posts

53 months

Tuesday 12th November
quotequote all
Hi,

Is anyone planning on fitting a new exhaust setup to avail of a more thorough sound from the new GT4 / Spyder.

Forgive me, I don’t actually know how the particulate filter works, but a few reviews have suggested that it dampens the sound of the car?

Twinfan

4,213 posts

52 months

Wednesday 13th November
quotequote all
I believe they're incorporated into the headers - they need to be hot to work. So you'd need a new full exhaust to remove them and then a remap to account for the different back pressure the engine now sees.

It's a lot of work and bye-bye warranty so I suspect most people will leave them well alone.

oo7ml

Original Poster:

191 posts

53 months

Wednesday 13th November
quotequote all
Yeah, I have no interest in doing so, as I like to keep cars in their pure form (i.e - I’m boring).

Thank for your help.

jh001

372 posts

125 months

Wednesday 13th November
quotequote all
oo7ml said:
Hi,

Is anyone planning on fitting a new exhaust setup to avail of a more thorough sound from the new GT4 / Spyder.

Forgive me, I don’t actually know how the particulate filter works, but a few reviews have suggested that it dampens the sound of the car?
The new 991.3 RS has GPFs and IMO sounds as good as the pre GPF GT3 so don’t worry too much!

oo7ml

Original Poster:

191 posts

53 months

Wednesday 13th November
quotequote all
Ok great, thanks... however the GT3 does have a larger rev range and scream :-)

Twinfan

4,213 posts

52 months

Wednesday 13th November
quotequote all
Very different exhaust system on the GT3, being rear-engined. The GT4/Spyder suffers more in the sound department because of the GPFs.

Porsche911R

17,900 posts

213 months

Wednesday 13th November
quotequote all
jh001 said:
The new 991.3 RS has GPFs and IMO sounds as good as the pre GPF GT3 so don’t worry too much!
it don't quite sound as good, but is still ok, and the reason it does still sound good is they removed the side mufflers.

they cannot do that on the GT4 hence the really muted sound.

gtsralph

883 posts

92 months

Wednesday 13th November
quotequote all
Twinfan said:
I believe they're incorporated into the headers - they need to be hot to work. So you'd need a new full exhaust to remove them and then a remap to account for the different back pressure the engine now sees.

It's a lot of work and bye-bye warranty so I suspect most people will leave them well alone.
I think you'll find they are separate and located away from the headers/manifolds near the rear box



Twinfan

4,213 posts

52 months

Wednesday 13th November
quotequote all
Thanks Ralph - I must be thinking of the GT3 setup?

thelostboy

3,668 posts

173 months

Wednesday 13th November
quotequote all
Removing any kind of silencing along the system will improve the sound. I'm sure it won't be long until aftermarket options are out.

Over in the States, manifold back systems were out very quickly for the previous GT4. People seem more reserved in the UK about doing bits when cars have a warranty. I guess in the States consumers are more litigious; it would be for example unreasonable and I understand not enforceable for a manufacturer to refuse to honour, for example, a repair on an engine issue if you had changed a part nothing to do with the engine.

Porsche911R

17,900 posts

213 months

Wednesday 13th November
quotequote all
thelostboy said:
Removing any kind of silencing along the system will improve the sound. I'm sure it won't be long until aftermarket options are out.

Over in the States, manifold back systems were out very quickly for the previous GT4. People seem more reserved in the UK about doing bits when cars have a warranty. I guess in the States consumers are more litigious; it would be for example unreasonable and I understand not enforceable for a manufacturer to refuse to honour, for example, a repair on an engine issue if you had changed a part nothing to do with the engine.
new rules and regs would make the car NOT road legal.

older cars not an issue I have exhaust parts on 2 cars they pass MOT's and are no issues and fully road legal

tricky times for newer cars hence the JCR GT3 system changes parts after the filter on the new GT3.

gtsralph

883 posts

92 months

Wednesday 13th November
quotequote all
Capisto seem to have a GPF delete for 992 but whether it includes necessary ECU changes to cope with differential back pressure and temperature I don't know. I'd want to be very sure any hardware change to Euro 6d GPF exhaust plumbing was properly supported by mapping

Taffy66

3,091 posts

50 months

Wednesday 13th November
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The only aspect of the warranty Porsche can legally enforce with a aftermarket exhaust fitted, is they will refuse to extend the original warranty unless car is 100% oem..There's a lot of misinformation and scaremongering in the UK no doubt spread by the OPCs themselves.
I'm fitting a JCR Titanium exhaust to my RS with GPFs next year and might also delete the OPFs as well..The biggest obstacle is to inform your insurance company and make sure they include it in the certificate should the worst happen..

gtsralph

883 posts

92 months

Wednesday 13th November
quotequote all
Porsche911R said:
...tricky times for newer cars hence the JCR GT3 system changes parts after the filter on the new GT3.
Agree with this, messing with the GPF without understanding how it operates is a risk.

thelostboy

3,668 posts

173 months

Wednesday 13th November
quotequote all
Porsche911R said:
new rules and regs would make the car NOT road legal.

older cars not an issue I have exhaust parts on 2 cars they pass MOT's and are no issues and fully road legal

tricky times for newer cars hence the JCR GT3 system changes parts after the filter on the new GT3.
What rules and regs? And how is this tested at MOT?

It's a restriction. A GPF is the same as a DPF, but for petrol cars. I don't see what's complicated about it. Especially for a 992 being turbo, as less back pressure is good news.

I remember when people panicked about cats... proved an absolute non issue. You can also pass an MOT without a cat, as long as you meet emissions.

Also remember someone cited about messing with the 991.1 GT3 exhaust would make the engine blow up when the car was launched! Turned out it was just the 997 exhaust anyway.

Would like to see some proof, not just hearsay.

Twinfan

4,213 posts

52 months

Wednesday 13th November
quotequote all
thelostboy said:
What rules and regs? And how is this tested at MOT?
I'd like to know this too. Can someone explain it please?

chrisABP

961 posts

96 months

Wednesday 13th November
quotequote all
So whilst not strictly speaking illegal to modify your exhaust you can potentially come unstuck with the police if your driving and car is deemed to be a nuisance. Think young idiot driving his modern 4-cylinder turbocharged hatchback with no silencers and an awful 'pop-bang-crackle' re-map and you get the idea..... Not entirely sure what the criminal offence would be but it wouldn't be 'you've changed your exhaust' and would more likely be 'you're making a noise by driving like a ****'

From an MOT test point of view 'Exhaust noise levels in excess of those permitted' can now be a MAJOR FAILURE. Note the words 'can be' as it would be at the MOT testers discretion after he has assessed the exhaust noise during the emissions test for the vehicle or by revving the engine to around 2,500rpm OR half the maximum engine speed if this is lower on vehicles not subject to an emissions test
The DVSA book specifies 'Exhaust noise from the vehicle must not be unreasonably above the noise level normally expected from a similar vehicle with a standard silencer in average condition'

It would take a very picky tester to fail your GT4/GT3 etc on a bypass being fitted, lets be clear unless he has an identical car with a standard exhaust sat outside to compare how could he judge it was unreasonably above the level normally expected from a similar vehicle with a standard silencer in average condition??? And if the DVSA were to carry out a spot check on the tester during said test they too could not prove it to be any louder either so testers discretion wins.

My advice - fit the upgrade, enjoy the noise and use an MOT tester who lives in the real World and has an element of petrol flowing through his veins! Thankfully I employ 3 such testers! LOL

Porsche911R

17,900 posts

213 months

Wednesday 13th November
quotequote all
thelostboy said:
I remember when people panicked about cats... proved an absolute non issue. You can also pass an MOT without a cat, as long as you meet emissions.
any car without a remap would throw a cel with no cats. I also doubt it would pass MOT emissions, hence why people fit race 200 cel units.

even 100 cel ones would cause a sensor to fail.

as for filters, Petrol ones will go the same way as DPF regarding MOT's I would guess and that's pretty serious.
"Owners who have deliberately removed particulate filters to improve the car’s performance face a bill of £1,000 or more.

why would they not bring that in for 2020 on GPF's to line up the same as DPF.

as it's been rushed in, the MOT rules will soon catch up after the emissions scandals I would say removing one will not be legal pretty soon.

or removing it, it might not pass the EURO 6 emission figures for that model anyway even if it were ok to remove it.

Twinfan

4,213 posts

52 months

Wednesday 13th November
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You're talking "ifs" and "mights".

So it's currently not illegal.

Porsche911R

17,900 posts

213 months

Wednesday 13th November
quotequote all
Twinfan said:
You're talking "ifs" and "mights".

So it's currently not illegal.
well if it don't pass the emissions figures for that model year then yes it would be.

It's not easy to get any answers atm.

I don't think a car needs a GPF if it can pass which leads me to think if you took it off it would fail.