Can some one help me understand the difference between dynos and why people get such different figures depending on wether its a hub dyno or a rolling road (if thats the two types). I thought i new the difference but after reading this thread

https://passionford.com/forum/general-car-related-discussion/265594-dennis-is-at-it-again.html

Im confused.


Why do you get different figures? Why is there more than one way to test the power, wouldnt one type of dyno make it easyer?