That one shows how much a really good tuner with experience can figure out on a dyno.
but what he figures out in that story would have been much more time, even a bit of tail chasing, if it hadn't been on a dyno.
I had an experience a couple of years ago on the dyno with an engine I didn't build and what it did and how it acted was a real head scratcher. I should describe exactly how it was acting and then post up all of the data and see if anyone can figure it out. The customer left with the engine and a couple of days later I called him up and told him what to look for-I was amazed that the dyno was able to tell me what was going on. Basically halfway through the 2nd pull it would drop 50-60hp. The first pull was something like 380hp and every other pull was 330hp or something like that. In the car this guy would have never ever ever figured it out.
Moral of the story is the dyno should be used for many other reasons and oddly enough HP/TQ is one of the last. J.Rob