Hello I talked to a few of my friends and well around my area car upgrades are a distant dream so many of us are lost in what to buy for cars. I'm not that interested in turbos or superchargers so what other upgrades can i get to improve the horsepower of my Mazda3. I was told that a new exhast would improve it by 15-20 hp? True? and what others like fly wheels and such? Sorry if I seem alittle off... its just upgrades such as these are hard to find. Thank you


- Nick