Nailed the neighbors mail box post with mine at about 50.  Broke everything up front and the upper chassis.  Upgraded to RPM arms and shiney shafts.  Not sure why, but it sounds turbocharged or blown now.  My guess is the shiney shafts.

I would stick with the stock manifold. It's not like you will be able to tell the difference between fast as hell and I can't see it anymore.