I have a 2011 Mazda 3 i-Sport with a manual transmission and a 2.0 L 4cyl engine. My warranty is up and I've been thinking about upgrading with some aftermarket parts. My research leads me to believe that the most logical place to start is with either a cold air, or short ram air intake, and upgrading the exhaust, however I've also read that upgrading 4cyl engines aren't exactly worth it and in some cases can do more harm then good.

If I'm looking for a little more power, is it worth it? If so what are some good parts to look at? (CA resident)

 

In the past I have used after-market parts and have been very pleased with them.

 

A good set of sticky tires is the best bang-for-the-buck mod you can get.

If you're set on an intake and exhaust, check out Corksport. They have a great rep.

http://www.corksport.com/index.php?d..._category_id=0

 

I agree with eggynatey regarding tires.