The OEM backbox mod sounds good, but if you start removing front cats or fitting a cat delete x-pipe, it's really loud and lots of drone.
The E9X M3 system we built matches (beats
) Akrapovic for performance for half the price and as you'll know even the factory system has a real drone at 2500-3000rpm. We spent a long time developing the E9X M3 system, adding Helmholtz resonance chambers to the rear sections to eliminate the drone as much as possible (something in development for the GTR systems also).
After we built the exhaust, many days were them spent incorporating knowledge drawn from standalone ecu tuning on this engine into the stock DME. The result was 465-475hp from a bolt on exhaust and an ecu reflash, and a seriously FAST car, very proud of this package and one I never get bored of driving
Please call us on: 01925 830889 (if we're busy in the workshop please send an email!)
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Visit us at: ACspeedtech, 3C Trident Ind.Park, Birchwood, WA3 6AX.
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