[CREWZIN]

Max,

A couple years ago on another forum (PT Cruiser World) one of the members had instruments to measure air flow and temperature. He tried numerous intakes and took measurements of different suggestions from other forum members and one of the best home-made intakes was one using the stock air box.

The 90 degree tube from the stock box to the hole in the fender-well was replaced by a larger PCV pipe that let more air in. There's two white donuts inside the air box and they were taken out because they restricted airflow and a K&N less restrictive filter was put in place of the stock air filter.

These few modifications produced cool air with less restriction into the throttle body. No hot engine air was introduced.

That's the best thing you can do to the stock 2.4 liter engine. It can't use a lot more air than is already getting in without major internal work. The cooler, free-er flowing air the better.

Forget gimmicks like the Throttle Body spacer and things like the Tornado. They don't do a thing for the PT engine.

Now if you want to make a little bit more noise while letting in more air, the Air-Raid System will do that but you'll pay for it out of your pocket. It's a good system as it also separates the hot engine air from the filter. Volant makes the same kind of system too.