Wow that has to be a tight squeeze!

I bet the stock POS accordian tube is squished down to about 50mm I.D.
Either way you still have Far too much filter for a small 2.5L engine.
You are getting less airflow, air straightening and velocity compared to an optimum sized filter.
There have even been dyno tests proving this before.
Running an oversized filter can actually hurt perfromance.