Engine/Transmission (1998.5 - 2002) Stacked power modules?

[DieselTorque]

what is meant by the term, stacked power modules/chips, how is it done? does it increase HP & tq numbers?

 

[Billy Diesel]

Stacked just means that you have two different types of boxes/chips in your truck. I have a VA (a timing box) stacked with an APB (fueling box). Timing generally helps the low end, while fueling generally helps the high end. Stacked together, the entire power band is modified.