Make sure it will withstand Underhood temps. I made my first one from PVC and after two Texas summers it went oval and would not stay sealed. I then went to a muffler shop and had a piece of 3" bent and cut and had them weld on the vacuum bungs on. I went to the dealer and bought another coupler like the one to the throttle body and used it to connect to the airbox. Works great never leaks and holds paint better than PVC and you can ding it to not hit the connector on the coils which you can't do with PVC.