Do the Japanese GTC models (2020) have OPF installed on the exhaust system? Do they bang and pop like the 2018 pre-facelift models?

Problem is that I own C63s from 2018 with amazing exhaust sound (original) and would like to buy GTC model from 2020 but the exhaust is so quite (European model with OPF).

 

Late reply (I stumbled upon this discussion by chance while browsing back through this section): yes, the AMG GT 190 facelift ('19 YM onwards) intended for the Japanese market are equipped with OPF (like those for the European market) and the sound is (unfortunately) less loud, as are the crackles...

 

Some soft-tune can improve the soundtrack of the GTC.

Here is a non-aggressive strategy to increase crackles and burbles on AMG GT’s with OPF (Gasoline Particulate Filter).

AMG GT models equipped with OPF/GPF have factory-suppressed crackle logic because OPF requires cleaner combustion, excess unburned fuel damages the filter and EU noise regulations limit overrun behavior. So even in Race mode, OPF cars produce much milder burbles than non-OPF cars.

BUT, a careful, gentle ECU calibration can restore nice, tasteful crackles without harming OPF longevity.

For a safe, OPF-friendly tune, the tuner should:

- Slightly retard ignition timing on throttle lift creates small afterburn events without overfueling.

- Add a minimal increase in overrun fueling, just enough to trigger soft burbles, not loud bangs.

- Shorten duration 1–1.5 seconds of burble is safe. Not the long 3–5 second “machine-gun” style (dangerous for OPF).

- Keep EGT (exhaust temperatures) within OPF-safe limits ( limits burble activity when EGT rises)

- Preserve catalyst safety limits by not disabling of cat protection maps and not disabling of OPF temperature monitors.

- Maintain factory lambda targets under load so rich-misfire maps or fuel dumps are strictly avoided.

.. and if possible, limit the changes to Sport+ mode only.

You can also add an Exhaust Valve control module (like Renntech EVM) to keep exhaust valves open when you want more sound.

What you must avoid are: Hard burble maps, pop & bang “gunshot” style tunes, excessive timing retard, rich-misfire strategies, anti-lag, unmetered extra fuel dump on overrun, Cat/OPF temperature monitor deletions and OPF delete pipes (unless racing only).

Check tuners like Renntech (US), Eurocharged (US), MSL Performance (UK/EU), or GAD Tuning (EU) and tell them you want “Soft Overrun Enhancement — OPF Safe / No Aggressive Burble Maps”

Keep us updated if you perform any of these.

 

The OPF really mortifies the otherwise wonderful sound of all engines, and in particularly this V8...
I don't know if and when I'll be able to buy a facelifted GTC/GTR, but if I do, I'll definitely remove the stock OPF/downpipes and reprogram the ECU to let the engine singing again...

 

I hear you. I’m not sure what the penalties are in every country for running without an OPF, but whatever you do, don’t try it in Germany.

 

I know that in Germany they are very strict about this, and even more so with foreigners... Here in Italy, fortunately, they are a little more tolerant (but not too much).