These, I just went through my receipts to double check.
http://www.summitracing.com/parts/sum-g9040/overview/
Sometimes I have to wonder if things fit differently from biscuit mounts to spool mounts. I have never had an issue with them scraping and I purposely went over some speed bumps, slowly of course, in a parking lot not too far from me and they never hit, big bumps too. Last time I measured ground clearance was with the 14's on there and I had around 7" from the bottom of the collector.