9000k

What is the best intake for my 8? Anyone have any ideas?

Jaguar_MBA

Your car comes stock with a cold air intake system.

Read everything on this website....Racing Beat's intake is well designed.
http://www.racingbeat.com/FRmazda4.htm

Also the K&N Intake (2nd version) is good. The 1st version actually reduced HP per some members.

http://www.rx7store.net/category_s/124.htm
http://www.knfilters.com/search/appsearch.aspx

kw1k

AEM CAI all the way, screw the rest.

Rotor Kreuzer

Mazdaspeed CAI prob'ly coming out in January.

rotarygod

I personally endorse only the Racing Beat system as it is actually a well developed and designed system but many others will endorse others as you've already seen. Which one is "best" is really a matter of personal opinion. None of them will give you a power gain that you will actually feel.

mikeb

rb is probably the best bet at this point
maybe the ms cai will be good though