So, im debating whether or not i want to get a cpe cai for my 2004 mazda6.
i was doing some research on it. and it says you can get optional parts: Bypass Module and Water-Repellent Pre-Filter.. are these necessary parts? i read somewhere that if i take out the cpe intake or disconnect the black box that the car wont start? is this true?

 

The only way your car won't start after removing the intake is if you don't put the airbox back in. As for the black box, i'm not sure it's all gonna depend on how it splices into the cable. Regarding the bypass, and water-repellant things, they are not required, and depnding on the area you live in, may not be necessary. The water repellant sock would be a very good idea to get if you live in an area where it rains a lot. The bypass is only necessary if you are in an area that floods alot.
If you are after a decent entry level, bolt-on power adder, I'd say go for it. The things work great, and sound awesome too.

-Cameron Keffer