Boost = pressurized air,
Its measured by a pressure sensor which translates it into an electrical signal for the ECU to understand.
Bolt-ons increase the overall efficiency of the motor, either by cooling the pressurized air, reducing restrictions on the intake side or exhaust side.
Originally Posted by E90Company
-You don't increase boost through bolt on's, it's increased through a tune. The factory DME will actually increase boost on it's own at higher altitudes, in order to reach the factory load target.
Boost isn’t increased, the wastegates stay closed longer, to reach the same psi number, so you still get the same amount of boost but the engine has to work harder to get there.
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