AMG GT OPF Delete

AMG GT OPF Delete

Author
Discussion

WhyTwo

Original Poster:

1,154 posts

206 months

Sunday 30th March
quotequote all
I've been following the market for some time and am now in a position to buy an AMG GT. I test drove a 2019 GTC yesterday. This GTC ticks every box except 1...

It just doesn't sound how an AMG GT should. There's no pops or crackles on the overrun. It just sounds like it's been muted. This is in Sport+ mode with the exhaust valve open. Part of the reason for wanting an AMG GT is the firebreathing V8 and the noise it makes.

Coming from a tvr Cerbera who’s exhaust note is intoxicating, the pops and bangs on the overrun often making me lol, this is massively disappointing.

Looking in to it, it seems the OFP filter is the issue and the solution is to delete/remove the OFP filter.

Is this the case? If so, has anyone done this? Is it a simple task? Is any remap required? Has it caused any issues? Does it mean issues with MOT?

Edited by WhyTwo on Sunday 30th March 17:28

Faszination76

84 posts

58 months

Monday 31st March
quotequote all
WhyTwo said:
I've been following the market for some time and am now in a position to buy an AMG GT. I test drove a 2019 GTC yesterday. This GTC ticks every box except 1...

It just doesn't sound how an AMG GT should. There's no pops or crackles on the overrun. It just sounds like it's been muted. This is in Sport+ mode with the exhaust valve open. Part of the reason for wanting an AMG GT is the firebreathing V8 and the noise it makes.

Coming from a tvr Cerbera who’s exhaust note is intoxicating, the pops and bangs on the overrun often making me lol, this is massively disappointing.

Looking in to it, it seems the OFP filter is the issue and the solution is to delete/remove the OFP filter.

Is this the case? If so, has anyone done this? Is it a simple task? Is any remap required? Has it caused any issues? Does it mean issues with MOT?

Edited by WhyTwo on Sunday 30th March 17:28
So - deletion of the OPF's is a straight MOT failure. It's my understanding that to remove them you'd need to go for a catless downpipe setup and a remap, the former of which itself is also an failure of course.

I have a similar issue on my E63S (2018 W213), although i'm in a slightly better position in that the previous owner removed the mufflers so I do get more volume (still not enough) and pops and bangs. However, I used to own a W205 C63S and that was MUCH louder in all respects, because it was a pre-facelift car (2017) and OPF's weren't mandated at that time.

I'm not sure if all GT's came with OPF's or of a similar situation exists, in that if you were to search for a pre-facelift car, you'd get one without OPF's to begin with. The only obvious thing to be conscious of doing that is that spec will be different between newer and older cars.

I'm sure a friendly GT owner will be along shortly to confirm or deny my comments smile

WhyTwo

Original Poster:

1,154 posts

206 months

Monday 31st March
quotequote all
Thanks for your post. Interesting in regards to the MOT. Is this due to emissions? I know all about this, having had a Cerbera for 13+ years!

Faszination76

84 posts

58 months

Monday 31st March
quotequote all
WhyTwo said:
Thanks for your post. Interesting in regards to the MOT. Is this due to emissions? I know all about this, having had a Cerbera for 13+ years!
Yeah I’m assuming emissions, they were mandated by the EU a few years ago and are being put on everything.

Such a shame really, uncorked the M177/178 engines sound incredible.

Which Cerbera did you have? I always wanted a 4.5 but couldn’t justify it, still love the sound of them now (on the rare occasion I see one).

WhyTwo

Original Poster:

1,154 posts

206 months

Monday 31st March
quotequote all
Faszination76 said:
Yeah I’m assuming emissions, they were mandated by the EU a few years ago and are being put on everything.

Such a shame really, uncorked the M177/178 engines sound incredible.

Which Cerbera did you have? I always wanted a 4.5 but couldn’t justify it, still love the sound of them now (on the rare occasion I see one).
Mines a 2004 4.2, which is actually a 4.5 bottom end. It's up for sale on PH at the moment (the black one).

MoT time is always 'interesting'

Benson11

79 posts

178 months

Tuesday 1st April
quotequote all
IIRC the OPF's arrived with the facelift and the earlier cars have a bit more noise about them. Personally I wouldn't sacrifice all of the other facelift upgrades for the noise.

Removing the OPF's will no doubt increase the sound but will likely cause some MOT issues. Fitting/swapping cats in and out isn't going to be a sensible option. Check out on YouTube Chirs Slix recent video of him fitting upgraded turbos and some Chinese decat downpipes, they looked a right pig to fit with the engine in situ. Maybe some other parts options might be easier to fit?

Other options could be leave the OPF/cats alone and look at modifying the rear silencer.

Jon39

13,749 posts

157 months

Saturday 5th April
quotequote all

WhyTwo said:
I've been following the market for some time and am now in a position to buy an AMG GT. I test drove a 2019 GTC yesterday. This GTC ticks every box except 1...

It just doesn't sound how an AMG GT should. There's no pops or crackles on the overrun. It just sounds like it's been muted. This is in Sport+ mode with the exhaust valve open. Part of the reason for wanting an AMG GT is the firebreathing V8 and the noise it makes.

Coming from a tvr Cerbera who’s exhaust note is intoxicating, the pops and bangs on the overrun often making me lol, this is massively disappointing.

Looking in to it, it seems the OFP filter is the issue and the solution is to delete/remove the OFP filter.

Have you considered one of these? GT8
No OPFs.





You will have all the wonderful exhaust sound that you could ever want.
The exhaust valves in factory mode are automated, but full control can be organised, including closed for occasional circumstances.

In the pre-2019 Vantage range, there is quite a wide choice from V8 to V12S.
Perhaps the pinnacle is a GT12 model.
Same concept as an AMG GT, with front mid-engine and rear transaxle.

Present values probably now mean very reasonably depreciation from now on.


WhyTwo

Original Poster:

1,154 posts

206 months

Monday 7th April
quotequote all
I did consider a V8V. They do sound amazing, and are pretty good value right now. My issue with them is the interior, it's a mess! I couldn't live with it.

I've gone for a 2017 GTC Edition 50. No OPF delete required.

Zippee

13,744 posts

248 months

Friday 11th April
quotequote all
WhyTwo said:
I did consider a V8V. They do sound amazing, and are pretty good value right now. My issue with them is the interior, it's a mess! I couldn't live with it.

I've gone for a 2017 GTC Edition 50. No OPF delete required.
Good choice 😀
We have a very good and active WhatsApp owners group and Facebook page (AMG GT Owners UK)

WhyTwo

Original Poster:

1,154 posts

206 months

Tuesday 15th April
quotequote all
Zippee said:
Facebook page (AMG GT Owners UK)
I've just joined it. Thx for the heads up

peteA

2,730 posts

248 months

Thursday 17th April
quotequote all
WhyTwo said:
I did consider a V8V. They do sound amazing, and are pretty good value right now. My issue with them is the interior, it's a mess! I couldn't live with it.

I've gone for a 2017 GTC Edition 50. No OPF delete required.
This - just took my 2017 GTC roadster out today and it sounds awesome! The pops, cracks and bangs are a laugh…which can be toned down if needed with the press of a button.

I had a 4.2 AJP engines cerbera which was de-catted and boy did that car pop and bang! It was liked a machine gun…a loud one! Great car

Calza

2,063 posts

129 months

Saturday 19th April
quotequote all
WhyTwo said:
I did consider a V8V. They do sound amazing, and are pretty good value right now. My issue with them is the interior, it's a mess! I couldn't live with it.

I've gone for a 2017 GTC Edition 50. No OPF delete required.
Top choice, the noise will be absolutely superb!

WhyTwo

Original Poster:

1,154 posts

206 months

Tuesday 22nd April
quotequote all
peteA said:
I had a 4.2 AJP engines cerbera which was de-catted and boy did that car pop and bang! It was liked a machine gun…a loud one! Great car
My Cerbera is a 4.2 AJP. It's recently been decatted. The pops and bangs are fantastic!