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Removing the Governor on the 200SX

For those of you not familiar with the governor on the 200SX, the ECU cuts the fuel at 109mph. Regardless of how fast the speedo reads, you are actually doing 109mpg when it shuts the gas off. The governor is very, very accurate, however, the speedo is not extremely accurate, thus it may say you are going 115mph, etc.

>I think this is the wrong approach. Most governors or speed limiters
>basically cut off additional fuel (probably from the EFI unit)
>disabling any attempt at further acceleration. I can understand your
>assumption, if you say had an automatic, but 5-speed are for the most
>part, mechanically free from electronic intervention (i.e. the ECU).
>Good luck and tell me what you come up with as an alternative..

Comments by Rob Microys

We've beat this topic to death on the list before. Yes the limiter can be disabled by disconnecting the Vehicle Speed Sensor on the transmission. It will also disable the speedometer. The only way to effectively disable the top speed limiter on the stock ECU is to develop a circuit (between the speedometer unit and the ECU) that will send a fake signal to the ECU (eg a steady 110 mph, regardless of actual engine speed) once the signal from the vehicle speed sensor is above 110mph. I have researched this a little, but have not had time to get a scope on to the ECU's VSS line to check the incoming signal.

The only problem is that the VSS is used by the ECU in some situations for ignition timing and fuel delivery. Although this would allow for the speedometer to remain functional, the ECU might not be accurately delivering fuel to the injectors. But just cutting the wire from the speedo unit to the ECU, you will fire off a DTC and light up the MIL in the dash... not all desirable. My best suggestion is to get the ECU from JWT. I was thinking about making a speed limiter removal circuit, but that's on hold for now...