Nervy said:
I had thought of a gruppe M, but it’s a bit much for me, alas alas.
The sound of the GruppeM doesn’t compare with the aFe!
I ran an aFe intake for a decade and replaced it only because the heat shield started to corrode. I bought a GruppeM because I have one on my B7 RS4, where it sounds immense. It looks great under the bonnet of the Zed, but the sound is very disappointing after the aFe intake and my RS4 experience.
Compared with the aFe, the GruppeM is much more muted and far less aggressive. The aFe produces a guttural sound from 4k rpm and really brings out the S54 scream closer to the redline. The GruppeM doesn’t do either.
A number of years ago, I followed an unsilenced quad bike into a tunnel about 80-100m behind it. I took my Zed from 3-8k rpm and the sound of the aFe intake had the rider craning his neck to look over his shoulder despite the racket he was producing.
I’m still running the GruppeM but with a sound generator similar to that in the non-M Zeds so I can hear the intake a little more in the cabin. The volume is better than it was, but it’s still missing the vocal range of the aFe.
I have Remus back boxes which are louder than OEM but passed noise regulations at every track I visited when I lived in the UK and easily pass here in Sydney too. These and the aFe intake complimented on another in terms of volume and tone, but they drown out the GruppeM in some parts of the rev range.
Nervy, my advice would be if your priority is to improve the appearance under the bonnet, then stretch to the GruppeM. If you want to appreciate the incredible sounds produced by the S54 across the rev-range, then buy an aFe and don’t be disappointed that you didn’t pay more for an aurally lesser experience.