Tuesday, March 27, 2007

Woo Hoo Stage 2!

Well, I finally broke down and spent all that part-time job money I've been amassing. I went and saw Jon up at Flatirons Subaru and purchased a COBB AccessPORT V2 with a PROTune by Super-Rupair's own Harvey, a front set of Hawk HPS front brake pads, a set of Goodridge stainless steel brake lines, a liter of ATE Super Blue racing brake fluid, and just for kicks a Mr. Dampachi doll from Tein. Besides wheels and tires, I am pretty much set for the track day put on by Flatirons Tuning coming up June 2nd. I just needed to get all the parts installed and set up my tune date.

A quick overview on the COBB AccessPORT for those who aren't familiar with it's capabilities can be found here. I would highly suggest downloading the latest firmware update when you bring your AccessPORT home before you install it in the car.

The original plan was to not install the AccessPORT until I took it up and had the ProTune done by Harvey. Then, I started thinking that it would be nice to be able to document the difference in the car with the COBB stage 2 map vs. the custom tune that Harvey was going to do. The thing that sealed the deal was my Check Engine light came on a few days after I installed the downpipe and cat-back exhaust. The CEL is caused from the rear O2 sensor readings being off from what the computer says they should be. Basically, when you install a high flowing exhaust system on these Subaru's the rear O2 sensor readings differ enough that the ECU thinks that there is a problem with the catalytic converters in the downpipe, and thus illuminates the Check Engine light. Some Subaru's are more sensitive then others in this regard. I've heard of people driving thousands of miles and the light never comes on, for some they only drive a few minutes after installing an exhaust system and it comes on. The AccessPORT, when installed, removes that code from the ECU so your Check Engine light goes out...or so I thought.

I reflashed the ECU using the AccessPORT instructions. Cobb requires at least a high flow downpipe for their Stage 2 map. They highly recommend a catback exhaust as well. On top of those two items I have a catless uppipe which improves things farther. This is known as Stage 2+ in the Legacy world. I chose the Stage 2 (91 Octane) map and in a few minutes the car was ready to drive. A quick test drive found gobs more power under the right foot. Boost increased from 13-14 PSI stock to about 16-17 PSI tapering down to about 13 PSI at redline. The car used to run out of juice above about 5500 RPM, but with the Stage 2 map from COBB it pulls like a madman all the way to redline. 100 mph comes up before you even know it, and the acceleration from 60-100 mph is crazy! I can tell from the smell of the exhaust at idle that it is running much leaner, no more stinky fuel smell from the pipes. The best thing about this is that there is no decrease in driveablity. Coming from the DSM world where you basically have to live with a car that idles rough and dies out occasionally in order to make decent power, this is quite a welcome difference. Absolutely the best "bang for your buck" mod out there for these cars.

One minor problem came up the next day as my silly Check Engine light came back on. I checked the codes using the AccessPORT and it was that stupid rear O2 sensor reading wrong again. I found that the code translated to the rear O2 sensor seeing a "low" signal. I thought that was odd since usually the codes are for "high" readings by the sensor. I did some research on the LegacyGT.com forums and found a guy that had the same code and found that the wires going to the sensor had been damaged. I put the car up on a lift and found that one of the wires had gotten rubbed through by the driveshaft and was broken. A quick wiring repair and a few zip ties to make sure it doesn't happen again and the light hasn't come back.

Overall I am very happy with the car at this point. The extra power really makes the suspension mods and better tires needed ASAP. I'll cover those in the next installment, as well as the dyno numbers with the base map (stock) vs. the COBB stage 2 map vs. the custom tune done at Super-Rupair.

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