Higher line pressure in the Allison transmisson is the key to holding more power and before this could only be done through a TCM tune. BD's Allison Pressure Controller allows you to hold 25%-115% more power in a easy plug-n-play module. No more having to flash the TCM computer! Delivers up to 275psi of line pressure at WOT. The pressure controller is only active when boost is over 15psi so no parasitic load or extra heat will be created when inactive. Installs in under an hour.