Do the throttle body bypass and you will see a noticeable difference. As for the exhaust, I went with the HKS which is bolted in three locations. Never had an issue.

Thanks for the info on here - I just got my 2010 3 in July and signed on here to see what the best updates were. So far I've got the K&N filter and a straight pipe, these I could basically do myself and that I thought would provide the most performance. What to do next...I still got a little money to spend.

how were the gains on the filter and straight pipe? i already have the cai and might just do the exhaust system right now and hold off on the headers depending on the gains

Hi Guys, I just got myself a Mazda Speed 3 2.3. i'm looking to de-cat, does anyone know if i can just de-cat or am i going to have to do some sort of software to make the car "think it still has the cat"?