Har ikke prøvd metoden selv, men her er en cut-n-paste:
"I hope to explain well because my english is not so good...
The speed cut on the gen.III ecu is set at 185km/h
If you cut the wire going to the ecu you obtain 3 results:
1 - no speed cut
2 - turbo VSV no more energized (no overboost = less hp)
3 - check engine ligth will go on when you pass 90-130km/h
So you can't simply cut the wire but you have to feed the ecu with a speed that is less than the real speed.
The 4024 is a frequency divisor; the cost of this chip is less than 1$. It can divide the input frequency from 2 to 128 times.
This is the wiring connection that i have used. I installed this chip 1 month ago and i don't have any problem.
4024 pin #
1 ----> from speed sensor (cut the purple-white wire going on pin 9 ecu E6; 22 pin connector)
2 ----> Ground
7 ----> Ground
12 ----> this is the speed/2 frequency from chip to ecu pin 9 E6; 22 pin connector (other side of the purple-white wire )
14 ----> pin 1 ecu E7; 16 pin connector - don'cut this wire, connect only! (+5v)
If someone wants to translate this write-up in good english i will be happy...."
Alternativ er vel f.eks. en Greddy Speedcut Defencer.

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