Shoulder Belts Installation?

I thought i remembered something about belts needing to not be able to slide side to side, but re-reading the rules i can't find it. Am i missing it?

Our belts are just wrapped around the harness bar. Passed tech twice in 2012 that way.

The need for essentially no side-to-side movement arises from a combination of this part of rule 3.5:  "When viewed from above, shoulder harnesses should be closer at their mounting points than at their seat-entry points" and this part of subsection 3.5.3:  "All sliders should be snugged up to their mounting plates or harness bars as much as possible."

Page 15 of the "How Not to Fail the Safety Inspection" guide is a bit out of date on this point, as it says that the belts "must go straight back or angle in toward center" but the current ruling is that "straight back" is not sufficient, as "should be closer" is now interpreted as "must be closer."  Our belts wrap around the harness bar and are prevented from sliding outwards by some adjacent rollbar padding zip-tied in place; this arrangement passed tech last season.

That's how I take it, too.  My point is simply that by the time one has complied with the spacing requirement of 3.5, combined with 3.5.3, the result is effectively no side-to-side motion, even though there's nothing in the rules explicitly forbidding side-to-side motion.

If one has a curved harness bar like this (we do), it's conceivable for the outboard belt's loop point to move forward and introduce slack. Therefore you need to put some kind of clamp on there to prevent that. We have a fancy clamp like this on the Neon (thanks, Kent!) but did the cheaper muffler-clamp-around-padding-scrap on another car.

All three of these should fail tech because the tail needs to be 100mm (4") long. During an impact, the buckle will slide back to the mounting point and slack will pull through the buckle. With a mere fraction of an inch, the webbing is at risk of sliding through the 3-bar buckle.

Yes, there are many problems here. First, the 3-bar buckles are not doubled-back. They are as good as not attached. Second, there is about 6" of slack between the buckle and the mounting point. After an impact, the 3-bar buckle will be at the harness bar, giving you an additional 12" of slack. You are now dead. Third the seat is too far from the bar. A seat brace is needed if this were a race car. Fourth the harnesses are not restrained from side-to-side motion, and as noted the outboard one is at risk for sliding around the curved end of the harness bar. Fifth, without dimensions, it appears from the picture that the shoulders harnesses should be anchored right next to each other. Much farther back and they should be crossed, at least if a HANS is to be used.

See page 18 for HANS; page 28 for no HANS. Note that  for the HANS calculation, "X" is measured from your shoulders, not the seat back:
http://www.schrothracing.com/sdocs/2009 … ctions.pdf

We had welded tabs on our harness bar (professionally done). Evil John mentioned that the wrap around the harness bar style was preferable to the welded tabs, although we passed tech by him with no issues.

We wrapped our belts around the harness bar, and they always stayed where they needed to be. We didn't use any rollbar padding to hold them from sliding out, but that does sound like the easiest and cheapest idea. We might implement that next time just to be on the safe side.

@TheEngnieer -- Yes, we're on the same page. Sorry -- I didn't at all mean to imply that you hadn't noticed these things. I was just reinforcing and elaborating on your points.