Dynos don't read the same between them. Easily doctored. Logs are logs.
I don't agree. I have never seen anyone show up for a tune with a Vdyno that matched their first pull... ever.
First off, it is very rare for a tuner to try to actually fake a dyno run, their credibility is at stake and its a business, they don't care about the results of 1 car owner out of the 500+ cars they tune every year.
Second, a dyno facility is a controlled environment with more variables being consistent than logging on a road. Vdynos are not accurate at all if you are looking for power numbers, repeatability, sure... as long as there are no changing variables (which there always are)
Third, other than Mustang dynos most same make dynos within the same area will read the same. the atmospheric conditions are close, elevation as well, air quality etc... I can say this from experience running a car on multiple dynos within 4 hours on the same day and the same makes of dynos were all less than 1% difference. Similar tests done with a few different cars on at different times, so the test results were repeatable. This was performed on cars from 400-900whp so any percentage difference would be a large hp number.
You guys are arguing about proof that was provided... he gave you factual data from a dyno run. While you can choose to disbelieve it you certainly shouldn't argue that it isn't factual and then try to discredit the data provided from a controlled environment with a tool designed specifically for tuning and providing that power data.