An ungoverned 500E will reach 165 MPH, which is also redline. With a gearing change it will go 175 MPH, drag-limited. Only you can decide if the extra 10 MPH is worth it, but I'd see if your car even has a speed limiter (I know several 500E owners that claim their cars are unlimited).

Apparently an ASR defeat switch is not so easy to create, which explains the cost of these devices. You can elect to defeat ASR by disconnecting the front wheel speed sensors, but in doing so you also kill ABS.

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"If God had meant for us to walk, why did he give us feet that fit car pedals?" Sir Sterling Moss

Michael
2014 E63S Estate
2006 SLK55
1995 E500
1986 Porsche 944 turbo