Product Description
The Blow-Thru Boost Tube is intended for use on Subarus which are using aftermarket turbo chargers that can "outflow" the stock intake system. It replaces a PERRIN front mount intercooler boost tube with one that is larger and accepts the factory MAF sensor, relocating it from the intake system to the the boost tube, allowing the ECU to read more air flow, in turn allowing the tuner to tune beyond 450WHP!The Blow-Thru Boost Tube has a BigMAF built into it which requires ECU re-calibration in order
to run properly on your vehicle. This BigMaf is designed to do two things: 1. Allow your ECU to accurately measure airflow above and beyond what the stock intake can measure.
2. It is sized specifically to offset the use of 800cc fuel injectors.
Air leaks such as a disconnected vacuum hose or a loose or popped off boost tube are dangerous as they can cause severe engine damage or leave you stranded on the side of the road. The PERRIN Blow Thru boost tube moves the MAF sensor to only a short distance before the throttle body therefore allowing the ECU to compensate for any leaks in the system saving your engine.
The MAF sensor is very sensitive, and things like fans turning on and blow off valves venting can significantly alter the readings of the MAF sensor. This will cause the car to run erratically at idle and cruise situations. The Blow-Thru boost tube locates the MAF sensor in a smooth straight section of the charge air, making a consistent airflow readings, improving drivability.
The Blow-Thru Boost is designed with a larger pipe diameter right at the MAF housing. With proper tuning, this allows the ECU to read more air entering the engine without maxing out sensor voltage, allowing ECU mapping to 550WHP+. Tuners can start with maps built for the PERRIN BigMAF intake system, easily transitioning from short ram intake to Blow-Thru intercooler. This part does require ECU tuning and will not function correctly when installed on a stock tuned ECU.
The BOV is normally located after the MAF sensor in the boost system. The Blow-Thru boost tube relocates the BOV fitting before the MAF sensor allowing drivers to use vent to atmosphere (VTA) blow off valves (BOV).
Pro tuners now have the option of simply removing the Subaru intake and running a filter directly off the Turbo. No intake system is needed as the MAF sensor is now located within a boost tube.
