After 700 km on the new performance high flow airfilter in my 9-3, here's the update:

Initially:
car feels really sluggish, hears the "whooshing" air flow, definitely lots of air coming through the intake. Step on the gas hard in automatic mode, boost needle never inches pass the middle portion of the boost gauge. Shift into manual mode, car hesitates during the first and second gear, never pulls as hard in 3rd (like before I put in the performance filter). Gas consumption went from 10.2L/100km to 10.8L/100km.

Decided to put the car through "boost" learning sessions. I live high up on a hill, so everytime I go up the hill, I step the gas pedal hard and hold the car in between 3500rpm and 4000 rpm. Initially boost needle still does not come close to the red region.

After 700km, car now runs smoothly and accelerate hard even in automatic mode, boost needle now tips the red region when pushed hard. Boost comes on strong and early, torque comes on stronger than before I put in the new filter. When in manual mode, I am even able to spin the front wheels on 1st gear. Gas consumption back to 10.3L/100km.

Engine T8 probably needs time to "learn" how to handle the 40% increase in airflow. It's original factory settings were tuned for the airflow coming in through the stock paper filter. Factory Fuel/air mixture settings were probably not optimal for the increase airflow and T8 not being A.I., took quite some time to "recompute" what the fuel/air mixture setting should be to accomodate the increased airflow over the whole rpm range.

Overall, the 9-3 pulls stronger in all rpm ranges, even in auto mode on the sentronic. :D

Very good to hear, strange how this car learns and interprets and everything else. did u go ITG or J&R?

Very good to hear, strange how this car learns and interprets and everything else. did u go ITG or J&R?

I think either JR or ITG will perform equally well. The only difference is in the longevity of the filter. I believe the ITG lasts longer without cleaning and reoiling, due to it's depth filtration foam design. I ordered the ITG.

This is interesting mav, I have noticed the sluggishness too and will attempt to do more proactive 'training' like you suggested.

im getting my ITG filter next week ... so thanx for preparing me for the slugishness part :) but how sluggish is it at first? what does exactly the car do and how bad is it?

Mav, how do u rate the filter compared to the old normal one?

im getting my ITG filter next week ... so thanx for preparing me for the slugishness part :) but how sluggish is it at first? what does exactly the car do and how bad is it?

Mav, how do u rate the filter compared to the old normal one?

I have a sentronic, so I am not sure how it would affect it if you had a 5-speed manual.

Anyway, the car in auto mode, felt like it didn't want to rev up readily, and the boost needle never went past the middle part of the gauge. You step on the gas hard, and the car responds very slowly. The gas mileage was really bad initially.

Now, the car seems to have "learnt" how to work with the increased airflow, and in both auto and manual mode, I can push the car hard, and it responds with a definite rush and rumble (coming from both the turbo and my magnaflow exhaust) and the boost needle tips the red line now. But I notice that I don't have to give it much gas to raise the turbo boost now, which I thiink is why I am getting back to 10.2L/100km with spirited driving.