I'm new to the group and starting to look into some acceleration and mileage enhancements to my 2003 HCH with MT. Aha - it sounds like you just got the filter element. Did you look into a whole cold air intake system? Is anyone aware of one available specifically for the HCH? I'm wondering if a kit for a regular Civic could be modified.

Changing the filter element could make a difference, but adding a cold air intake system (also called a forced-air induction system) would make a much bigger improvement, albeit with the tradeoff of louder intake noise.

I also want to look into a cat-back exhaust system. Does anyone have any information on those?

Dan