[Zeke]

It's not the belts as much as it is the seat. Sure, you could cinch down on the belts so tight that you don't move, but that's not the point. Get a good seat like the Renagade. A 3" lap belt won't be noticable when worn. Any shoulder harness will as you cannot lean forward at all. There is no inertia system available. The anti sub belt should only be used with a seat made for that application. Search over on the 991 BBS. There is a belt system that they use which is OK for AutoX, but not rated for time trails or racing. Sort of a higher safety rating for street. I hate the serach function here or I'd do it for you.