TB-Denso is a Tuning Box to fit all Distributor style injection pumps like the Bosch VP-44 and Nippon Denso. We mainly use this system on early Toyota vehicles and it has adjustments available inside the end cap cover. Adjustment should not be required as the unit will be supplyied pre-programmed to suit the vehicle. It is connected via four or five wires. On Toyota 1HD & 1KZ engines, all wires are connected next to the ECU; no connections are made inside the engine compartment.