6pt mounting with Harness bars

[illwillem]

I know this has been touched on a couple times but not answered directly. Those of you that have harness bars with 6pt anti sub belts, how are you routing them?


1. Routed back through the lap belt holes and clipped into eyelets in the threaded provisions on the harness bar.

When you get in the car you effectively sit on top of the 6pt straps then clip them into the cam lock. apparently this is called 'formula style'

or

2. Route them through the bottom seat hole under the seat and back to the same eyelets on the harness bar.

In my initial attempt to follow the instructions to the 't' I bought the hardware and FIA backing plates to mount to the floor but it turns out the prescribed locations on the floor pan are dimpled and would cause the plates to not sit flat enough to spread the load- thus leaving me the two other options.

Scroths exact wording (attached below) is rather ambiguous and throws in PREFERABLY in regards to the anchor point needing to be 20* back from sternum line, and since the harness bars were designed with these provisions which is better




Profi 6-point and Hybrid[SUP]TM[/SUP] models
· Anti-submarining strap routing shall be vertical down from the groin, preferably approximately 20° back.
· Anchor points shall be approximately 100 mm [4”] lateral apart from each other. In case of a low seating position (e.g. in open wheel race cars), this separation may be reduced since the anchor points are closer to the thighs.

Profi F-models
The anti-submarining strap routing over the upper thighs and attachment to the shoulder belt latches with the buckle in between, does not provide a direct load path from the shoulder belts down to the anti-submarining strap anchor points. The indirect routing requires a type of preloading of the anti-submarining straps during a frontal impact. This is achieved by sitting on the anti-submarining straps, routing them rearwards and attaching them in the region near or on the lap belt anchorages.

This anti-sub strap design requires sitting on the straps or having a thin seat panel allowing the straps running rearwards right underneath the driver’s buttock.

 

[TURBO2GO]

following this post... I am about to install mine.

 

[itrsteve]

Oh sweet death bars. Nothing like being pinned in by a harness in a car without a rollbar.

I really wish I could talk you people out of using these.

 

[Stephen@NCAutoUSA]

I know there's some debate but Itrsteve. What if we have bucket seats and no air bag. Any advice there other then putting the airbag back in and stock seats?

- - - Updated - - -

Since I'm looking into safety equipment in the future and titanuim Dave's harness bar and a 6 point is what I was "planning" on down the road

 

[1K2GO]

Your 1st option makes no sense to me and would never pass a SCCA or NASA tech inspection.

I have Recaro Pole Positions w/6pt Simpson camlock harnesses on both sides w/harness bar. The 2pt. sub is routed thru the bottom of the seat & back under, then both ends are harnessed to the lower cross brace behind my seats. As long as the harness is threaded properly it passes tech every time without issue. I can take pics tomorrow if requested.

 

[Stephen@NCAutoUSA]

Ok. Yeah if you could post a pic or two I think it'll help.

Now what if my seats don't have a hold for the bottom belt/belts that are really 5 and 6 point harnesses?

 

[illwillem]

1K2GO do you have the ends of the sub straps secured using clips to the eye bolt or or do you have them wrapped around the lower bar itself like the shoulder straps are on the upper bar?

 

[docjohn]

I'm not racing.My hpde setup is a 5 point with the sub strap bolted through the floor and up through the oem seat which was cut and restitched.The lap and shoulder belts are mounted to comptechs older system which bolts to rear seat mounts and oem lap belt anchor.

 

[Hrant]

Previously posted in here as post #57 ...............

 

[1K2GO]

Hrant, subs routed under your seat cushion and over your seat bottom would never pass anyone's tech inspection. think about what that would do to you in a frontal impact.

I will post detailed pics later this afternoon.

 

[TURBO2GO]

Robert as many detailed pics as possible please. Thanks

- - - Updated - - -

Oh sweet death bars. Nothing like being pinned in by a harness in a car without a rollbar.

I really wish I could talk you people out of using these.

Still better off than with a 3 point IMO. Yes a rollbar is ideal. This has been discussed many times. I've come up up with my own streetable cage design that still allows targa removal and has side impact beams. But it ties in the rear and front hoops together down the center. T-top style. Also hugely stiffens the chassis

 

[Hrant]

Hrant, subs routed under your seat cushion and over your seat bottom would never pass anyone's tech inspection. think about what that would do to you in a frontal impact.

I will post detailed pics later this afternoon.

Robert, if you follow the link of where the pictures are you will see the extensive discussion that led to this. And explain to me what will happen with frontal impact with that set-up. I am very planted with that ste-up and there is absolutely no submarin-ing that I can sense.

 

[1K2GO]

Robert, if you follow the link of where the pictures are you will see the extensive discussion that led to this. And explain to me what will happen with frontal impact with that set-up. I am very planted with that ste-up and there is absolutely no submarin-ing that I can sense.

Looking closer at the placement of your sub straps I am astonished that they let you run that way. A qualified tech inspector would never let you on the track like that. I have failed tech for far less. What they are looking for ideally is a sub strap or straps that falls forward of the buckle or cam lock and drops straight thru your seat to the floor where it is anchored by a bolted & welded eyelet. Obviously, they are willing to accept less optimum set-ups on street cars but IMHO yours crosses way over line and could result in causing additional injuries. Just my opinion H, take it for what its worth, after all, its your funeral Just kidding!

My set-up, although not optimum and technically not to the letter of the rules, will pass SCCA & NASA tech and I am comfortable with it.
Without removing the seat, these are the best pics I can come up with.

 

[Hrant]

Robert, I trust you read through the thread I referenced. Putting all hype aside, there is absolutely no requirement as far as safety is concerned that the sub belt must pass under the seat and through the seat as your is. Yours is one option. Sitting on the sub and looping it through the thighs is another - which is why they make that option per the OP's second picture.

Per my post in the referenced thread, you will note that I have indeed consulted with Simpson. My set-up is not ideal in the folowing respects: (a) the 20 degree angle for the side belts is not achieved; I am more like 40 degrees given that it is anchored to the base of the harness bar and I suspect yours is the same; (b) this leaves us with the second less than optimal scenario regarding how the sub is routed. In my case it goes through lumbar seat's lower opening and then I sit on it as prescribed. In your scenario, you routed in under the seat and presumable pulled it out the hole.

My potential "tension" is at the passage, yours would at the upward angle passing through the hole. To compensate for your set-up, some have opted to tie the sub to a cross bar. Besides (b), all the other issues are the same as far as I can surmise. And again, what concern do you have with submarin-ing concern since that is the purpose of the sub - given the second picture by the OP. I am open to reasoned discussion

 

[1K2GO]

One thing I'm confident of; mine's quicker :wink:

I'm not interested in killing this thread with a debate. If you're comfortable with it, so be it, but I'll bet you can't get it passed a qualified tech inspector.

 

[Stephen@NCAutoUSA]

What if you don't have that hole in your seat and come directly from the front? Would that be a safe option?

 

[Hrant]

What if you don't have that hole in your seat and come directly from the front? Would that be a safe option?

No> the angle of where the sub mates with the buckle has to be as vertical as possible. Looping it from the front will give it more like a 45% and will allow you to submarine to the front of the seat.

And Robert, the issue is not debating on such important and emotional concern to many, but rather helping Prime members understand when generalizations are made. As i said, I am open to a discussion that refutes the safety concerns. Indeed, You are quicker I grant you that :wink:, but then again I did not pour $50K and I still putz in style :tongue:

 

[Stephen@NCAutoUSA]

No> the angle of where the sub mates with the buckle has to be as vertical as possible. Looping it from the front will give it more like a 45% and will allow you to submarine to the front of the seat.

And Robert, the issue is not debating on such important and emotional concern to many, but rather helping Prime members understand when generalizations are made. As i said, I am open to a discussion that refutes the safety concerns. Indeed, You are quicker I grant you that :wink:, but then again I did not pour $50K and I still putz in style :tongue:

Ok, what's the best viable solution for me then if I'd like to put a 5 or 6 point harness in with titanium daves bar in the future and I don't want to switch out my bride gias seats because I like them.

 

[1K2GO]

Back in the day, I was a certified SCCA pro racing tech inspector. I saw all manner of crazy-ass concoctions disguised as race cars. The worst offenders were always the DD/street cars with bolt-on weekend warrior 'race parts'. There's a lot of interprutation of the rules going on at the track and sometimes its laughable and other times its just plain dangerous. Its the job of the tech inspector to draw that line and police the drivers and their cars. What really blew me away was when I'd see drivers taking there swiss army knives to there beautiful Ferrari or Cobra to get it passed. Don't be 'that guy' and plan ahead. You want to track your street car? You need to make the effort to get close enough to where your not asking your inspector to look the other way. To this day, I do my own visual inspection of all the cars in my group. That way I know who to be careful with and who I need to take serious. Some pretty crazy chit out there passing for track tools. Thats why I spent what I spent on mine, so I'll never be 'that guy'.

 

[docjohn]

In defense of Hrant, back in the day comptech recommended the under the thigh mount for the 6 point harness with their bar...so next time you see Shad ask him what they were thinking.

 

[1K2GO]

In defense of Hrant, back in the day comptech recommended the under the thigh mount for the 6 point harness with their bar...so next time you see Shad ask him what they were thinking.

Times change and so do rules. It was Shad that advised me to attach my subs to the lower rear cross brace of my harness bar and I've never been comfortable with it. This thread has inspired me to correct it.

 

[asylum]

In my initial attempt to follow the instructions to the 't' I bought the hardware and FIA backing plates to mount to the floor but it turns out the prescribed locations on the floor pan are dimpled and would cause the plates to not sit flat enough to spread the load- thus leaving me the two other options.

For me it is by far the best option.

 

[illwillem]

So I routed the the subs exactly as OK2GO had pictured. i still have the plates and the sandwich loops to run them off the floor but i think first ill need to figure out a solution to get them to mount flat. schroths engineering numbers are as follows ·

The pelvic movement combined with the shoulder belt forces will load the anti-sub straps to more than 6 kN [1,320 lb] each in a 5- or 6-point racing harness and can be intentionally higher in a F‑type model where the anti-sub straps are routed rearwards.

Im going to run some numbers on aluminum of the same thickness as our floor pans, it seems that 1320lbs and up is a LOT of load to place on the floor with out properly reinforcing it. The FIA plates are 3 1/2"X 3 1/2" and will spread the load, but are significantly reduced in that capacity when not totally flat, thats an awful lot of shearing force to place on a non structural part of the chassis. That being said im going to run the loops on the lower bar for now.

 

[1K2GO]

'OK2GO'? :wink:

 

[illwillem]

hah, im an animal on the keyboard, and my fingers work faster than my brain.