....Dyno's get a bad name.
Whilst looking for some info, I came across these graphs.
They supposedly show an R8 (Milltek) before modification and after fitting their cat-back exhaust.
Before.....
After.....
For those that don't know, if you look at the first graph, in the data at the bottom, you'll see 2 values. 'AT' and 'IT'. The 'AT' value is ambient air temp. This of course should be something like the current temperature. The 'IT' value is intake air temp. We look for a maximum deviation of 8°c between these 2 values. There's 28°c difference on this graph. The dyno will be applying a massive compensation as a result of this.
Also, that run was carried out in 'Shoot_8' mode, which is for 8-cylinder engines.
Now look at the second graph. Again, check the AT and IT values. AFPMSL. 76°c. That is just plainly insane. We'd use those graphs for nothing more than toilet paper. However, just as significant is the fact that the second run was carried out in an entirely different mode 'Shoot44', which is for 4-wheel-drive cars. So, with both plots on the one graph, comparison is just ridiculous and would make their work look better than it actually is.
Incidentally, the car only reached just over 80mph in the first graph. What's that all about?? LOL.