GR86 First MOT, Modified Cars, Future Emission & Noise Issues

Sixtoe

Sixtoe

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My 2023 GR86 just had it's first MOT, and one of the advisories was;
"Catalyst Emissions Limit Only Just Met"
Mine is fitted with the GR airbox and a cobra un-resonated cat back exhaust.

I was quite surprised at the fact it was only just under the limit, I've not had it tuned after running those things so could that be an issue? (and does that mean I have to spring for the whole ecutek thing?)

Also, this is... worrying? if anyone is looking to maybe play with mods in future;
https://www.evo.co.uk/news/209071/c...with-uks-tuned-and-modified-vehicles-targeted

This is also interested considering a lot of mods seem to want to remove the cat;

https://www.evo.co.uk/news/206327/g...-down-on-loud-car-exhausts-not-just-emissions

Be interested to see what anyone else thinks, I was thinking of turbocharging mine at some point, but now I'm wondering if this hasn't harpooned that...
 
I have the same mods as you: Cobra Non-Res and TRD Cold Air Intake. There is no requirement to tune with either of these. Nothing was picked up at my MOT for emissions in March of this year when it went into the dealership, maybe take it somewhere else?

The new regulations will likely restrict a lot of 'dodgy' mods, especially as it could lead to the keeper being prosecuted in certain areas like emission system tampering (which was always illegal anyway).
 
Do you occasionally give it the beans? I was always trying to get the best MPG I could while commuting but gave her the old Italian tune up more often in the lead up to my first MOT. I've kept up the habit! If the revs aren't getting high enough often enough I believe carbon deposits can build up which negatively affects emissions .
 
Renzokuken86 said:
Do you occasionally give it the beans? I was always trying to get the best MPG I could while commuting but gave her the old Italian tune up more often in the lead up to my first MOT. I've kept up the habit! If the revs aren't getting high enough often enough I believe carbon deposits can build up which negatively affects emissions .
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That's interesting, I got it done at somewhere quite a way away as I was on my way somewhere else and it'd been sitting on the motorway cruising for an hour...
 
Sixtoe said:
That's interesting, I got it done at somewhere quite a way away as I was on my way somewhere else and it'd been sitting on the motorway cruising for an hour...
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An hour on the motorway wouldn't be enough to result in any significant build up, it would be constant motorway cruising at low revs over months. I was so focused on getting an average 35mpg according to the car on my commute, hit the target and since I've dropped it to 34.1mpg 😂
 
The GR intake does move the position of the MAF, so it will impact AFR, its how some air intakes claim to make more power, not because they are better flowing but because they lean out the AFR, but in this case it shouldn't be by much, definitely not enough to alter the emissions that much, the short and long term fuel trims would take care of that.

Catalytic converters are very sensitive to temperature, maybe it just wasn't that hot when they did the emissions test?
 
ruled over by joyless jobsworths sadly.

1788469247821.webp


Proposed changes to emissions regs and testing are a concern in general given the potential for an older bone stock car to fail.

Fuel quality, atmospheric conditions, test method could all impact results. Owners like myself who intend to keep the car forever could find themselves unable to source OEM replacements for parts which fail entirely or sufficiently to not meet regs.

It’s an absolute can of worms for all older vehicles modified intentionally or otherwise. I’ve no doubt it’s as futile as trying to hold back the tide but I filled out the gov.uk consultation form disagreeing to all proposed changes and voicing the potential negative impact to the public and motor industry as a whole.

www.gov.uk

Regulating environmental impact of in-use emissions of road vehicles

www.gov.uk www.gov.uk
 
This is very interesting, Ensuring my car passes emissions tests is why I have been so specific with my front pipe selection and ended up getting one custom made and shipped from the US. I'm taking mine over to an old friend's garage to get emissions tested next week in leu of it's first MOT. He used to build the cars for a drift team and he's got some crazy Japanese cars, so I hope it comes back with tread on the rear tyres still :LOL:
 
Sixtoe said:
Be interested to see what anyone else thinks, I was thinking of turbocharging mine at some point, but now I'm wondering if this hasn't harpooned that...
Click to expand...

Without wanting to sound like an unpaid advertiser for JDL, their turbo kits have a 400CPSI cat in the downpipe, so might end up being the best choice for the emissions conscious UK GR86-turboer. apparently they're RHD compatible.
 
GRistopher said:
Without wanting to sound like an unpaid advertiser for JDL, their turbo kits have a 400CPSI cat in the downpipe, so might end up being the best choice for the emissions conscious UK GR86-turboer. apparently they're RHD compatible.
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That sounds really interesting, I'm wondering if it's going to force all UK tuners to do that as well anyway.
I'll be very interested to see how yours goes on the test :)
 
GRistopher said:
Without wanting to sound like an unpaid advertiser for JDL, their turbo kits have a 400CPSI cat in the downpipe, so might end up being the best choice for the emissions conscious UK GR86-turboer. apparently they're RHD compatible.
Click to expand...
I’m starting to sway toward a JDL catted header. I’d wanted to stay EL as I’m not a fan of the “subie rumble” but it’s looking like trying to improve performance and not fall foul of emissions testing is a massive pain. Apparently the HKS carted EL header is good for a performance boost but not effective enough to keep emissions in check.

If losing the OPF coding it off and switching in a catted down pipe would work for an NA application I may look at going down that route.
 
I’m half expecting my Navara, with its combined DPF, EGR, AdBlue deletes and Stage 1 remap to maybe not get through its MOT after the new regulations kick in, but we’ll see. I’ve primed the wife that she might be getting a new petrol hybrid Pickup truck next year and funnily enough she’s quite happy! 🛻
 
I'd assumed any decat or DPF/GPF/Adblue deletes were already MOT failures "by the book", if the tester identifies their absence. Visual check so you can core delete them and pass with a shell assuming your welds are good. Depends how closely the testers look / friendly, etc. and ECU maps would be impossible to detect 'visually'.

My read of the consultation on this point is they're wishing to substantiate public opinion; that the current car regs already cover this, for vehicles that come stock with cats/DPFs.
 
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