Williams Performance M140i exhaust system
Our 3.5" turbo back exhaust is now done.
The first customer was Pure Turbos, who wanted it for their Pure800 equipped M140i.
As they have their own rolling road they done a back to back test with the previous exhaust they were using.
1st exhaust was a full Remus system with catless downpipe, this made 464hp. The exhaust system was then changed to the full turbo back Williams Performance exhaust and ran on the same dyno with exactly the same BM3 stage 2 OTS map. Our exhaust gained an extra 20hp and 20nm!!! And this is over an already catless exhaust.