Well I blew another Stock bellow on my drivers side uppipe. This is the second one in a year. No rubbing just cracking at the bottom bellow connection. My question is I know everyone runs headers or manifolds but I know of a few instances that after changing from stock manifolds and uppipes trucks have went slower. I'm wondering if the tow flows would do the same thing. I really want to upgrade but don't wanna loose at the strip so that's why I steering away from manifolds right now. Any thoughts? My mods are listed, the truck dynoed 650/1070 at the end of may.