Originally Posted by roastbeef
i love these threads and breakdowns, thanks for sharing.
i do have a few questions;
1. does the full Akrapovic Evolution titanium exhaust system delete or replace any catalytic converters and/or trip any check engine lights? (basically, is it cali smog legal)
2. does bmw put up a fight with warranty claims with under drive pulleys?
1. The full Akrapovic EVO systems will trigger a CEL, a tune or delete-r module is needed to remedy this.
2. While BMW can theoretically challenge any
aftermarket part vs warranty, I have not heard or seen any issues vs warranty denial being contributed to pulleys to date on the S65.
Most times, the dealer doesn't even notice them.
Originally Posted by aka_phox
whats the gains with just the pulley and stage 2?
Here's a detailed thread about the MS UDPs:
Bang for the Buck Mods: Macht Schnell UDPs & Dyno Findings
And another showing the Macht Schnell intake only, as well as with UDPs and the Akrapovic systems on 2 M3s:
Macht Schnell UDP/Stage 2 Intake & Akrapovic Dyno Findings
Hope this helps!