I'm actually running Hedmans,72 Duster w/PS,no issues. No dinging or bending,had the engine in and out a couple timess with no help.Got my T-bars cranked down pretty good and been over numerous speed breakers with no dragging. I have Edelbrock heads and Schumacher poly mounts if that makes any difference. I have heard complaints about them,but I don't have any...maybe I just got a good set