Has anyone else experienced this?

When viewing my datalogs from the strip the VSS is always way slower than the actual speed achieved. Any reason why this would be? The gear ratios are correct in the s300 software, no other anomolies i can see....

Its reading about 65% of the indicated trap speeds. For example on the datalog it read 79mph, on the timing slip 123mph.

Any thoughts? as im not sure if anything else could be affected by this...

 

Thoughts? You're in the wrong forum.
Engine Management and Tuning

 

Is the car a import ? Is the s300 set to mph or kph ? Try setting it to the opposite of what its on.