Sadly, I have made a mistake. The math to calculate WHP is wrong. The correct math would be as follows. 500/.75 (the 75 percent that made it to the ground) = 666.666666666666667. We will round that to 667. This would mean that you actually need 66.7 lb/min of airflow.
You can double check this by multiplying 666.666666666666667 * .25 and you get 166.666666666666667 now subtract 166.666666666666667 from 666.666666666666667 and you get 500. That would be your number to the ground. Reading the Compressor map stays the same you would just plot the point at 66.7 instead of 62.5.
A Big Thank You goes out to Jafro and Joey (@TDC) for providing me with a few pictures needed to make this video possible. Yes, the meth kit belongs to Jafro so now you can make him put it on something 😉
This video ventures into reading a compressor map of a turbocharger. This video only refers to the Compressor wheel, so I can not stress enough that bench racing would be a bad idea when just reading the map. It is a good tool to determine what the compressor wheel is capable of on its own but your motor, cams, manifolds, etc may be a restriction causing the compressor to be less productive.
On the other hand, you can use this tool to see how well the compressor will suite your goals and to see how much room you have to grow. I hope that this simple explanation will help you correctly match a turbo of the correct size for your goals to your car.