There was a post recently referring to a Car and Driver article that explained why even these issues might not get the best performance out of a modern car on the dyno. The bottom line was that, like statistics, you can get the numbers to say whatever you wanted depending on how you massaged them. In this case, depending on the time of day the dyno was run, or the speed of the airflow across the bow of the car, or the temperature of the air blowing onto the intercooler, the output of the car in question (in the article a highly-tuned BMW M5) varied by almost 120 whp! That is a friggin' lot!
I don't need a dyno to tell me that my car is fast. What I need the dyno to tell me is how much absolute change from my baseline has each successive mod added. This, you can take to the bank. All the other numbers essentially not worth the time or effort.
Besides, do you want a dyno-queen or a real, live road warrior?
R
