A few details about the Banks Brake:
Much effort has been put into the design to ensure that airflow is not compromised while the butterfly is in the open position (when the brake is not in use). Remember that your truck operates under power much more than it operates under braking conditions. In order to accomplish this improvement in airflow, a number of things have been done. The size of the outlet bore is much larger than all others: The stock outlet measures about 2. 660”, PacBrake and BD measure about 2. 900” and the Banks Brake is 3. 120”. But outlet bore is not the whole story. You really need to account for a complete cross-sectional flow area, since you are also introducing a butterfly into the picture. The Banks Brake has a cross-sectional flow area that is nominally the same as the factory outlet, while both BD and PacBrake are substantially more restrictive.
The butterfly is also moved downstream, away from the turbine wheel. This has a profound impact on the function of the turbine wheel. Exhaust gases are coming out of the spinning turbine wheel in a helix fashion. If a butterfly is introduced too close to the outlet of the turbo, this has a negative impact on the wheel and can actually hurt turbine response. By moving the butterfly downstream, the turbine is allowed to operate as intended. We have received numerous reports of better low end torque and better turbo spool up with the use of the Banks Brake, a natural occurance when turbine efficency is improved. The shape of the casting also addresses airflow. It is designed as a conical diffuser, which means that the internal diameter gets progressively larger, which also encourages proper turbine efficiency. When the engine has been modified for more power, the airflow issues become even more important, and we hear from our customers not only about better power with the Banks Brake, but also reduced EGT’s.
The outlet of the brake mates to either a 4” to 3” adapter for stock exhaust systems (one cut required, no welding required) or a 4” turbine outlet pipe designed to mate to a Banks 4” exhaust, or other 4” exhaust (some slight modification may be necessary depending on the system).
But the device is ultimately a brake. It is designed to provide maximum braking efficiency (which will vary depending on whether you have a 24-valve, 12-valve with stock exhaust valve springs, or 12-valve with upgraded valve springs). We use a fixed orifice design that is calibrated at the factory so that no adjustment is necessary by the installer, eliminating the possibilities for error that could cause engine damage. A fixed orifice also does not vary during the life of the brake.
The Banks Brake for a 24-valve mated to a stock exhaust is $895, which includes a stainless turbine outlet pipe. Prices for other systems (12-valve w/ stock springs, 12-valve with upgraded springs, variations that mate to 4” exhaust) will vary, but that gives you some sort of an idea when making comparisons. When you consider the additional content in the system, the price is very competitive.
Hope this is helpful.
Peter Treydte
Banks Power
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