Project Gen 3STi: Testing the COBB AccessPORT


We chose to dyno the car at the well respected shop of AMS in West Chicago Illinois. We also chose AMS because we did not just intend to do a before and after dyno of the AP, we also planned to tune the stock car and wanted someone who would do things the MotoIQ way! The beauty of the AccessPORT is that not only does it come pre-loaded with maps an experienced tuner within the COBB Pro Tuner network can perform a fully customized tune that can be stored on the AP along with all of the other maps. While we were VERY happy with the results of the off the shelf map we wanted to see what was possible with a vehicle specific tune to showcase just what the AP could do. About a week before our appointment in true professional fashion Mitch McKee from AMS sent me an e-mail to get the details on what we would be doing during our session. I told him we were going to take a stock STi and tune it with an AP. He graciously accepted the challenge and the date was set. I use the word challenge because as simple as it may sound often times it is tough to improve upon an already good tune with no other supporting mods. Time would tell if Mitch could squeeze anything more out of the car above and beyond the COBB MAP.  


Mitch McKee from AMS works his magic. We hope he makes the car “highly unlikely to blow up!”

When we arrived at AMS we pulled around to one of their two AWD dynamometers. We would be using a Mustang dyno for this and all future testing for the sake of keeping things consistent. A swarm of AMS shirts swarmed over the car: properly securing our Subaru, placing fans and setting up the dyno. Special attention was paid on getting maximum airflow to the intercooler through a dedicated blower with the proper ducting. In less than 10 minutes the car was ready to be put through its paces. Mitch stepped in with his trusty laptop and began to work.

AMS does things right with a dedicated TMIC blower!


The first order of business was to put down a baseline and man was I nervous! Seriously why should I be nervous running a STOCK car on the dyno? The fates were with us as we did two baseline pulls in 4th gear and took our readings. In the interests of ring land preservation we chose NOT to do any more stock pulls. The car was very lean during the CL/OL delay and knock was present in MANY places. On the AMS Mustang dyno. our car put down 216 peak horsepower and 212 peak lb ft of torque with peak boost being logged at 15.1 PSI. We are NOT concerned with how this compares to other cars on other dyno.'s, only what our car put down in stock trim on THIS dyno as it will serve as the measuring stick for all future modifications. 

UMM yeah look at the AF ratio under CL/OL delay…


After being quite pleased with the fact that we did not oil down the rollers by ventilating the block, we used the AP to re-flash to the Cobb Stage 1 93 Octane MAP. We then spun the rollers again to the tune of 231 HP and 265 lb ft. with peak boost being 17.1 PSI. This is the dyno. we used in our 53 lb feet increase claim! In all honesty with that kind of increase in performance, economy, and drivability we could have left it at that, but sitting on the roller's at AMS with their resources behind the wheel there was no way that was going to happen.

COBB gets it right. In 10 minutes you can have this dyno curve on your previoualy stock Subaru…



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