will i void my waranty if i install borla exhaust and k&n filter in my 8?

Do a search. There have been many posts regarding this question.

The short answer is no.

long answer is maybe.....

those are the performance upgrades which I have done. I have been to the dealer several times for recall/warranty items and they hav never given me problems. You will however void the warranty on your exhaust system because you basically don't have it anymore.

The longer answer is that if any modification you make causes the problem, you are out of luck. An exhuast is not likely to cause you many problems. Dealers, however, don't have to perform any warranty work if they don't want to. The warranty is through Mazda, not the dealers. So if you dealer really wanted to, they could just turn you away.