The only way you will be able to adjust from 20 hp to 200hp is by varying boost pressure. They only things that can do that with the push of a button are turbos, or that procharger. The positive displacement blower is a very good option for these trucks because of one main thing, torque. Positive displacement blowers, like the Whipple, make full boost right from idle and big torque number down low. These trucks are big and heavy and torque is needed to get them moving. From my reading on here JDM seems to have the best handle on tuning them.