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Discussion Starter #1 (Edited)
Hello,

I have been enjoying my beast recently and I did a few (when and where possible) high-speed runs. Typically, the traffic did not allow me to really let it go as fast as possible, and I had to start braking from speeds around 260-270 km/h.

Once, however, I have managed to let it run long enough and I have experienced a very unpleasant and unexpected halt (loss of power) at speed around 275 km/h (on the dial) ... so my natural reaction was to release the gas pedal and slow down. Since then I have never tried to get to that speed again - as you can imagine I have got a little worried!

Could this be the speed limiter? My car is supposed to be delimited!

Could this be a clutch slip? I presume that the load on the whole drive-train is enormous at these speeds!

BTW, the car is very stable at those speeds (probably thanks to PSS9) and the engine was still pulling hard, i.e. it does not take many seconds to get to these speeds from some 150 km/h ;)

any similar experiences?

THANKS!
 

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The speed limiter cuts the fuel gradually but effectivley. This causes the car to stop accelerating but effectivley rock between 155 and 157 mph - for example. This is quite gentle but noticeable. It is nowhere near as violent as hitting the rev limiter.

If it were clutch slip im sure you would have noticed it. At those kind of speeds with those kinds of wind pressures I would expect the rev's to be shooting up as the clutch slipped.

I would say that you were on the speed limiter.

My elementary explanation of course.

Neil
 

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The speed limiter cuts the fuel gradually but effectivley. This causes the car to stop accelerating but effectivley rock between 155 and 157 mph - for example. This is quite gentle but noticeable. It is nowhere near as violent as hitting the rev limiter.

If it were clutch slip im sure you would have noticed it. At those kind of speeds with those kinds of wind pressures I would expect the rev's to be shooting up as the clutch slipped.

I would say that you were on the speed limiter.

My elementary explanation of course.

Neil
+1. Remember, the speedometer usually reads high, so 275 kph is probably around 255, where the limiter is supposed to cut in.

For the OP, I would check with whoever told you the car was "delimited". If so, it should hit well above 255 kph in real speed, probably 300 kph as read by the speedometer.
Regards,
Jerry
 

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I concur, on a speed-limited car the speedo indicates around 275 when you hit the speed limiter. No need to worry about your clutch...
 

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Discussion Starter #5
THANKS! So now I only have to really delimit the car - that is the easier problem to solve ;)
 
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