2016 Prius air filter

A very clear example of why we all need to pay attention to the complete maintenance schedule (not just the top section). My 2022 schedule specifically states in conditions such as you describe to inspect the engine air filter every 6 months/5000 miles.

 

Wix vs Toyota air filters



Depth below flat part of seal:
Toyota: 26mm with one small area at 27mm
Wix: uniform 28mm

Now this is the part that I didn't think to measure, but looking at the picture the pleats / filtration material on the tops, the Wix also looks like the filtration media is taller up there, too. There also seems to be more seal over-run on the top of the Toyota filter which would limit / restrict total airflow. The Wix seems to have more seal over-run on the extreme sides - which probably doesn't do any measurable thing to airflow.

Pleat count: below the flat part of the black seal,
Toyota: 69 pleats (+/- 1)
Wix: 74 pleats exactly

So none of this is exact science. If the Wix filtration media flows the same as the Toyota filtration media, then the Wix should flow better. If the Wix media is more restrictive, but only marginally so, then the Wix may still flow the same as the Toyota.

 

What does a slight increase in air flow do, with computer controlled fuel injection?

 

Mass air flow sensor senses more air flow, computer injects more fuel.

An owner can easily tell the difference in acceleration between a used Prius air filter and a new one.

 

There won't be any increase in flow. There might be an insignificant difference in restriction between those two filters when they're new. Any difference in filtering efficiency would be more significant.