BANKS DIESEL CHIP

The "boost tube" is actually a boost-bleed device. This is installed in the boost reference line to the wastegate actuator, and provides a controlled leak to atmosphere of the boost air signal going to the diaphragm portion of the actuator. Boost increases because the diaphragm does not "see" the full level of boost actually present in the intake manifold. But the real problem is that the actuator itself is a weak actuator, with only about 5 psi of pre-load, meaning that the wastegate will have the propensity to blow open under moderate exhaust backpressure. With a low wastegate-seat pressure, the wastegate will start to lift off of the seat prematurely. This kills the midrange torque potential of your engine. Ford uses a computer-regulated leak of their own to manage the boost at various rpms, sometimes as low as 5 psi and as high as 18 psi. The controlled leak that some diesel chip manufactures provide is in addition to the Ford valve, and will allow the turbo to achieve a higher..