Cobb Tuning Accessport For Lancer Evo VIII/IX

Tuning should never be taken lightly and not everyone lives within driving distance of a dyno and a reputable tuner. That's why companies like COBB Tuning offer safe mail order ECU reflashes for complex modern platforms like the Evo and WRX. The COBB AccessPORT system is basically a hand-held unit that communicates with the ECU via the car's OBDII port, allowing you to 'tune' your car in the driveway.

In addition to reprogramming the ECU with pre-existing high-performance tunes (downloadable from COBB's website), the system comes with multiple functions like DTC code scanning and real-time logging of engine operating parameters. Unlike a generic code reader, the AccessPORT allows much faster communication with the ECU at rates far exceeding the OBDII standard 2Hz refresh rate.

The temperature was 110 degrees F on our test day, which no turbo car likes, but our test car baselined at a corrected 254 wheel-hp and 243lb-ft of torque on the all-wheel drive Dynojet of Tuning Technologies (a southern California Evo shop). This falls right within the ballpark we anticipated for a stock car on this dyno. It takes under 10 minutes to copy a car's original map onto an AccessPORT and sync it with the car. Each AccessPORT 'marries' itself with the ECU and can only be used with one car. Once the factory calibration is stored in memory, the new tune can be flashed onto the ECU's permanent memory. You can easily revert to the original ECU program for trips to the dealership.

The AccessPORT programming also requires re-plumbing of the vacuum lines between the stock electronic boost solenoid and wastegate actuator. To better control boost, some pressure restriction orifices have to be bypassed, which allows for less boost oscillations with proper tuning. With just the California version of the Stage 1 software, we measured a peak of 270 wheel-hp, while torque remained almost the same, since most of the increase was well past 5252rpm. From what we could gather from the logs, most gains came from increasing boost by 1psi, while retaining the same profile and just slightly leaning out the mixture by a meager two-tenths of a point throughout the powerband. Since this was a conservative beta version of the final map, we think there will be more power to be made with more aggressive ignition timing and leaner mixtures.

To get a clearer picture, we had Tuning Technologies install the COBB air intake and turboback exhaust, and put the boost control plumbing and software back to stock, to see what gains hardware alone could make. The intake is a simple open-element cone filter with integrated venturi that adapts to the stock airflow meter. The three-inch COBB exhaust is quiet enough to pass on the street, but will get noticed at WOT. The increase in flow alone was good enough for a peak of 277 wheel-hp with the same torque and a mild gain in boost with a leaner mixture. Overall, the power and torque curve showed consistent and noticeable gains from as low as 5000rpm.

With boost control plumbing returned to COBB's configuration and Stage 2 software uploaded via the AccessPORT, we made a final pull to the tune of 302 wheel-hp and 265lb-ft of torque. Most of this power came from the healthy-but-safe 12:1 air/fuel ratio (that stretched all the way to redline) and roughly 21psi of boost. There was also a boost spike at 3500rpm that helped skyrocket power, right as the turbo got huffing, which trickled down to 15.5psi at redline to keep the engine safe.

While we see more room for power with this beta version of COBB's California 91-octane calibration, the end result of the Stage 2 package is still a healthy 300 wheel-hp made throughout the powerband. More than adequate for most street and track applications.

As the ECU maps are updated online, we're sure the Stage 1 and 2 re-flashes will find still more power.

If that's not enough, you can always flash the 100-octane maps onto your ECU's temporary memory, top off the tank with some race gas and go satisfy your ya-yas. Just make sure you switch back to the stock map when you put the pump swill back in.