2002-2007 Subaru Impreza WRX / STi

PERRIN Front Mount Intercooler users can now get a more accurate charge temperature reading and run a VTA BOV with no problems! Instead of measuring the Mass Air Flow (MAF) and air temperature before the turbocharger, the PERRIN Performance Blow-Thru boost tube moves the mass airflow sensor to the boost tube before the throttle body. The placement of this does many good things like allowing your ECU to read the actual charge temp the engine sees, which eliminates any need for a Cold air intake (MORE IN FEATURES). Also use Perrin's Vent to Atmosphere (VTA) Blow off valve with out running rich between shifts, or with out idle problems. (see ASM-INT-600)

The Blow-Thru boost tube also is designed with the Big MAF Intake in mind. Tuners around the world are familiar with this larger than stock MAF housing. This allows for the stock ECU to read more air flow, in turn allowing the tuner to tune beyond 550WHP! This also means the Blow-Thru boost tube needs to be tuned after installed. This part will not function correctly when installed on a stock tuned ECU.

This is for the STEALTH wrinkled BLACK blow-thru tube. Please search our store for the POLISHED and Signature Series wrinkled RED blow-thru tube.

Features

WHAT IS THE BLOW-THRU BOOST TUBE?
The Blow-Thru Boost Tube is a replacement of the large 2.75 tube in the PERRIN Front Mount Intercooler kit that relocates the MAF sensor into the boost tube. The way the MAF sensor works very simple, and it doesnt care, or know, if it is under boost or vacuum. This means the sensor can be placed in the boost system, or in the intake system, and function normally.

So... Why do I want this?

LEAKS ARE A PROBLEM OF THE PAST
The MAF sensor is normally located in the intake system before the turbo. In this situation, the turbo sucks in air, compresses it through the boost tubes, and pushes it into the engine. If there is leak in the intake system before the turbo (vacuum hose disconnected), it will cause the car to run lean and throw a CEL. If there is leak in the boost system after the turbo (boost hose loose, or popped off), it will cause the car to run rich and throw a CEL. Both situations are dangerous as they can cause severe engine damage.

With the MAF sensor located in the boost tube a short distance before the throttle body, any possible leak in the intake system will never be a problem. And being so close to the throttle body, most possible leaks in the boost system are not going to be a problem either. Also if you have ever had a boost tube blow off and leave you stranded, that is a thing of the past!

NO COLD AIR INTAKE
No more need for a cold air intake! The MAF sensor not only has the airflow sensor in it, but the air temp sensor is also located in it. With the MAF sensor/air temp sensor in the engine bay, it can read the high temps when your car is sitting still. Once you get going down the road, the temps drop significantly, but while waiting for your turn at the drag strip, or at a stoplight, the ECU sees these high temps. The ECU can then pull timing, and do other things that will hurt performance.

A short ram style intake doesnt loose power because the high temps that get into the engine, but rather from the high temps the ECU sees. At a stoplight, the high intake temps go through the intake, turbo, boost tubes, and intercooler before reaching the engine. The actual temp the engine sees is nowhere near this temp. So the ECU is pulling timing and changing fueling for no reason, as the engine doesnt see these high temps. With the Blow-Thru Boost tube this all goes away! Since it is mounted just before the throttle body, it will read the air temp the engine sees, and will make for more consistent tuning, driving, and power!