But it DOES matter what it reads. If you dyno says you make 950 HP and mine says 550 HP and in the car it runs like 550 then your dyno is worthless.
Horsepower is a calculated number, based of torque. Torque is easily measured. So that means HP is easily calculated. And if you correct for temp and baro then why all the different numbers?
Because the dickhead throwing the stick is a lying cheater. Seen this for decades. And the same thing with flow benches. You are measuring airflow. Why the ridiculous numbers? Because the guy running the bench is a lying cheater.
Numbers matter. And they better add up. All this bullshit that dyno’s and flow benches can’t all measure and read the same is a lie.
If they don’t, the operation is either stupid or lying.