Project Evo X GSR- Testing the K&N Cold Air Intake

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 Project Evo X GSR- Testing the K&N Typhoon Cold Air Intake
With its rear mounted turbo and tight clearances around the throttle body along with a strut tower brace that's in the way, the Evo X is one of the harder cars to install an intake on.  What is normally a quick job took about an hour. Oh my back!

As a caveat, the Evo X is notorious for not getting along with intakes unless the ECU is tuned around them.  The MAF or Mass Air Flow meter on the Evo X is very sensitive to location and orientation and many air intakes for the car on the market initially show a good power increase but also move the voltage output of the MAF around in response to the increased flow causing a big shift in the long term fuel trim of the ECU as the ECU tries to compensate for the shift.  As the ECU compensates the air fuel mixture becomes unacceptably rich, the power drops and sometimes a check engine light is triggered.

 Project Evo X GSR- Testing the K&N Typhoon Cold Air Intake
You would think that three experienced professionals could put an intake on quicker.  We spent most of the time arguing about how to do it correctly.  Then we read the instructions later…  Chris is complaining that race cars are so much easier to work on.  Naji is yelling to hurry up.

To evaluate the K&N Typhoon intake we asked our friend Naji Dahi of Looney Tuning to give us a hand.  Our first check was to establish a baseline.  Naji uses a software package called Virtual Dyno that is set up for a car's particulars such as weight, tire size, gear ratio and calculated drag.  3rd gear pulls are done along a controlled road with a nearby weather station for adding ambient condition data.  The Virtual Dyno software automatically calculates horsepower and torque from data extracted from EvoScan (a popular data logging software for Evos) output. Note that this uses actual logged RPM data and thus calculates power in exactly the same manner that a dyno does, not using an accelerometer which is dependent on the calibration, orientation in the car and accuracy of the accelerometer like many road dyno simulators.

 Project Evo X GSR- Testing the K&N Typhoon Cold Air Intake
Some things are better with two sets of hands….

The Virtual Dyno software developers have even designed correction factors to correct their output to match several popular models of dynos.  We selected the Dynojet correction factor simply because this is the most common dyno and this is what K&N used in their testing. Working with Naji we have found the road dyno software to be very repeatable to within 1-2 hp as long as we used the exact same controlled road area.  The repeatability between runs is what is important for tuning.

 Project Evo X GSR- Testing the K&N Typhoon Cold Air Intake
Mitsubishi thoughtfully glued some of the lines in place making it really hard to get them off, especially in the tight engine bay.  We had to resort to using a hook to break the seal around the tubes after Naji cut himself twice banging his knuckles around.  Chris does his Captain Hook imitation.

We test ran our Evo and found it to be extremely repeatable within a few hp per run.  We picked a power level right in the middle of our runs, not the highest or lowest. For a baseline the Evo X laid down 277 hp @ 6500 rpm and 276 lb/ft of torque at 4120 rpm.  Using an Innovate Motorsports LM-2 air fuel ratio meter we tracked our air fuel ratio at a rich 10:1 trending to an extremely rich 9.5:1 at high rpm.  We also monitored our long term fuel trim at 6.5% correction.

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