The only problem with using PVC pipe is that it will start to melt on hot days when your driving and things get hot. Also, it is really heavy. I looked into making mine outta PVC and found out that it melts and i bought some and it was really heavy. One day, I found this aluminum ducting stuff over at home depot and made mine outta that. it'* durrable and very light weight. then put a k&n like cone on it and it works great. my car sounds really nice now and i did feel performance gains. just a suggestion, to use something else besides PVC.Go Home Depot Performance!!LOL
Yea the pvc is heavier than aluminum. I didn't even think about getting a round duct. gonna have to pay home depot another visit.