Aftermarket Intake Cam and Exhaust Cam...are they both necessary to install at the same time? Are they both needed?

 

they are not both required for the install and not both neccessary depending on the cam and the setup you are going for.

I put just a 2001 ITR Intake cam in my car. I have hard of people putting a JUN stage 2 Intake cam in and leaving a stock exhaust cam.