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...

 

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

 

You probably have much larger than stock tires. This will give a lower indicated speed than you are actually going.

 

i think the kmh to mph could be a winner given that the conversion when done on a calculator was pretty much spot on!

No chance the tyres were making it be 50mph out! infact the speedo itself was reading pretty much spot on 1:1 too which is good!

 

Good, try it and report back !!

 

well ive just used one of the datalogs i had fromthe weekend and of course its changed the value in to km/h but i suppose thats not really solved the problem as if it was reading true km/H then it would be ~200. So i guess for now i need to call kmh mph for the purpose of this....odd!