Intake Air Bleed

Intake Air Bleed

The Intake Air Bleed function is intended for turbo-charged drag racing applications, where an air bleed valve is located after the turbo-charger to reduce manifold pressure. This is done to reduce compressor load, allowing the turbo to spin faster while staging.

If using a Mass Air Flow sensor for fuel or ignition tuning, the intake air bleed valve should be plumbed back into the intake after the Mass Air Flow sensor. Venting to atmosphere would make the ECU over-estimate how much air is going into the engine, causing it to run rich and interfere with ignition timing.

Page Contents

Wiring Tab

Connections

Intake Air Bleed

Select an available output wire, typically a DPO (Digital Pulsed Output) that will be connected to the Intake Air Bleed Valve.

Active State

Controls the direction of duty used to open or close the solenoid. Low will close the solenoid with 0% duty and open the solenoid with 100% duty. High will close the solenoid with 100% duty and open the solenoid with 0% duty. (Default = Low)

Settings Tab

Output Frequency

The frequency at which the duty signal will operate. Typically a value between 10 to 1000 Hz is used (Default = 23). Choosing low frequencies will create pulsations in manifold pressure because the air bleed switches on and off. Higher frequencies give smoother results.

ECU Navigator - Tables

Intake Air Bleed Table

The duty cycle you want the air bleed solenoid to act at. This controls how much the valve opens, and how much air will bleed out if there is boost pressure.

The input axis can be selected as anything you want by pressing F3 when the table is selected. Race Time is used as the default, but Launch Control Output State is also popular, with axis values 0 (launch control off) and 1 (launch control on). Typical table output values would then be 0% when launch control off and 100% when launch control on.

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