The Contour SVT does not have a speed limiter. Top speed is supposed to be 143 MPH as that is where it is "drag limited" or where there is no longer enough horsepower to increase speed.
The other Contours are speed limited to 118 MPH. The PCM cuts off the injectors to keep the speed at or below the limiter.
I have no idea what the limiters may be programmed to do for european use. It is possible that you hit a speed limiter, but it is also possible that you have a marginal problem (fuel or ignition) that only shows up under that kind of a load. It is also possible that you just "ran out of horsepower" to go any faster.
