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This is how to make your M135i sound like an M4

This M135i owner hacked into BMW's synthesised system to make his car sound like a 425bhp M4

Whether we like it or not, the practice of synthesising engine noises is becoming increasingly common in new performance cars. Sticking a turbocharger into the exhaust pathway and improvements to sound proofing have lead to a significant decrease in engine noise, much to the disappointment of many enthusiastic drivers. To claw back some of that aural involvement, manufacturers have resorted to this controversial system.

BMW's synthesised engine noises are played into the cabin through the car's speakers, so in theory, disconnecting your speakers should remove their influence altogether. But it was only a matter of time before someone went a step further and actually modified the synthesised sound.

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>Read - BMW M135i review and pictures

In this case, a tech-savvy M135i owner has managed to hack into his system and upload the soundtrack used in the new M4. It swaps the typically smooth straight-six soundtrack for a rougher, harder voice. You can hear it in the video above.

>Read - BMW M4 review, price and specs

If you want to listen to the M135i with its factory fitted synthesiser working, watch our track battle video below. What do you think? 

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