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The ECU has a speed sensor for reasons other than speed cut, also links to hicas control, power steering, idle controls etc etc...

Remap your ECU and get performance gains as well as removing or raising speed cut.

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I have a related question to this, since you guys are talking about what the ECU does and doesn't do with the speed signal.

Since I'm converting the car for use in the UK there's two things I need to do.

1) Convert the speedo to MPH

2) Get rid of the limiter, otherwise it's going to be annoying if I take it on the German autobahns.

I understand that the speedo is cable driven, but the ECU also gets a speed sensor reading, so my guess is that the speedo does the conversion from cable to whatever format the ECU is expecting? Is this correct?

The common way to do this conversion is to alter the data coming into the speedo, in this case that would mean a little gearbox that reduces the rate of rotation by about 5/8ths, you then get a black pen and scribble out the K in KM/H on the dash. This is going to mean that when I'm doing 80km/h the ECU will think I'm only doing 50km/h.

On my Legacy B4 I had this issue (that had a little box that altered the signal coming in from the sender on the gearbox), and it didn't seem to cause any problems, though you could see it was wrong if you used something like ECU Explorer to read the data from the ECU.

However you guys are talking about it breaking the idle control, power steering, HICAS and god knows what else. My car doesn't have HICAS but it does have ATESSA, is it going to create problems if I do this.

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https://www.sau.com.au/forums/topic/200886-limiter/page/2/#findComment-4224744
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