Seat belts

[ike84]

Ok, I need insight here.

For whatever reason, I've become paranoid that my 21 year old seatbelts aren't up to snuff. So I'm looking at options for replacement.

I realize the discussion of 3 pt, 4 pt, 5 pt, 6 pt is a long one and I don't want to start a debate about the pros and cons of each. What I'm really looking for is what is the safest option for a road car that sees WOT and a lot of curves.


OEM stuff is all 3 pt and allowed in a lot of racing applications.... But there is no safety rating on this stuff for racing, no age limits, and Porsche doesn't use high grade bolts for our seats or seat belt receptacle (hell, the receptacle is bolted to the seat rail which is an absolute no in most organizations!)

There are aftermarket 3 pt replacements for sale from China that are certified to EU regulations but not NHTSA or DOT. What's the deal with these? I'm skeptical.

Has anyone ever used the "3 pt" racing style (essentially a 4 pt where the shoulder straps converge)? It seems like these are gonna have the same issue as 4 point belts - submarining.

BUT - fia now certifies 4 pt harnesses?!?! What is up with that? I know schroth makes the 4 pt ASM systems that are DOT approved (and stupid expensive!) But I was surprised to find 4 pt cam lock models from sparco in their "competition" line that are FIA certified. Are we not worried about submarining any more?

Currently all my driving is street driving and I don't have a full cage, so I know that 5 and 6 point harness are really out of the question for my application. Maybe one day when my free time doesn't always come after the kids are in bed lol...

Anyway, all thoughts and experience are welcome and appreciated



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[ike84]

Ok, so apparently Takata's fia certified 4 pt harness have ASM features. Recaros website definitely doesn't mention this, and their pics don't show anything that would suggest ASM features of the shoulder straps. Takata's are again rather expensive ($300ish, similar to schroth)

It makes me wonder a bit about using a non-asm fia certified 4pt and simply sewing a "wrinkle" into the inboard chest shoulder strap (that's all the schroth ASM feature is anyway). Farm engineering safety features makes me a bit nervous though, albeit less so than random chinese 3 point retractable with an eu stamp on it lol.

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[Quadcammer]

I'm not sure I'd use even 4 points on the street. Without a hans system, I think you'd be less safe.

Your 21 year old seatbelts are fine when paired with the cars crumple zones and airbags.

[Burg Boxster]

Originally Posted by Quadcammer

I'm not sure I'd use even 4 points on the street. Without a hans system, I think you'd be less safe.

Your 21 year old seatbelts are fine when paired with the cars crumple zones and airbags.

Agree 1000%... 3pt OEM belts are designed to allow your body to articulate and dissipate "energy" in safest way possible in event of an accident. Thus their implementation versus old standard 2pt lap belts which put entire stress on lower spine (and face/neck via meeting of dashboard).

Likewise w/ 4,5,or 6 point harnesses without proper HANS device means your NECK becomes energy absorbing "crumple zone"... a tragic lesson we all learned 21 years ago with Dale Earnhardt's passing.

Stick w your 3pt system for street - 21 yrs old or buy OEM new if you want. I can't find rn but someone out of Germany did a fantastic video couple years back showing all various combinations and which is safest when. TLDR; 3pt safest for street. Harnesses when used w proper HANS.

Good luck

PSA to all: Please simply destroy your out of date 4/5/6 pt harness and do NOT put them on rennlist/craigslist/etc. They are too tempting for the tuner/Subie crowd. And yes, I know they are expensive but I'd hate to see anyone lose a life or be seriously injured b/c they wanted to look cool using improper restraints on street...

[/soapbox]

[ike84]

I certainly cannot dispute any of the points made there. I think it's a really interesting topic to learn about.

There are some good sources that strongly disagree with these points though. For example, a study done by the sae showed v type 4 point harness to be as safe if not more safe than 3 pt harnesses with no occurrence of submarining in their tests. This study assists limited though as the test numbers were small and the crash scenario was quite limited.

https://www.sae.org/publications/technical-papers/content/2003-22-0017/

And schroths crash test videos with the 4pt ASM belt are impressive to watch (although I always question when a company does research that so strongly supports it's own claims)

https://m.youtube.com/watch?v=EGrhJTSQRkY

Anyway, thanks for the replies. It's always nice to hear other people's insights and feedback.

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[Burg Boxster]

Ultimately, your body, your car, and therefore your choice. 4pt is generally done away these days in competition due to shortcomings of no anti-submarine.

SAE paper cited is, for all intents and purposes, 20 years old. Essentially same ERA as Dale Earnhardt's tragic passing when HANS was in its infancy and not yet mandated required equipment in NASCAR. There have been countless safety advancements since and suspect SAE has published numerous papers and/or standards since to supersede.

Likewise, Schroth video published by "Detroit Tuned" appears to have been filmed only in 4:3 aspect ratio... same as final episode of M*A*S*H

Finally, most "restraints" other than OEM 2 or 3 point are not street legal so best check w your state DOT guidelines before installing.

Good luck and be safe

Originally Posted by ike84

I certainly cannot dispute any of the points made there. I think it's a really interesting topic to learn about.

There are some good sources that strongly disagree with these points though. For example, a study done by the sae showed v type 4 point harness to be as safe if not more safe than 3 pt harnesses with no occurrence of submarining in their tests. This study assists limited though as the test numbers were small and the crash scenario was quite limited.

https://www.sae.org/publications/technical-papers/content/2003-22-0017/

And schroths crash test videos with the 4pt ASM belt are impressive to watch (although I always question when a company does research that so strongly supports it's own claims)

https://m.youtube.com/watch?v=EGrhJTSQRkY

Anyway, thanks for the replies. It's always nice to hear other people's insights and feedback.

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[ike84]

Originally Posted by Burg Boxster

Ultimately, your body, your car, and therefore your choice. 4pt is generally done away these days in competition due to shortcomings of no anti-submarine.



SAE paper cited is, for all intents and purposes, 20 years old. Essentially same ERA as Dale Earnhardt's tragic passing when HANS was in its infancy and not yet mandated required equipment in NASCAR. There have been countless safety advancements since and suspect SAE has published numerous papers and/or standards since to supersede.



Likewise, Schroth video published by "Detroit Tuned" appears to have been filmed only in 4:3 aspect ratio... same as final episode of M*A*S*H



Finally, most "restraints" other than OEM 2 or 3 point are not street legal so best check w your state DOT guidelines before installing.



Good luck and be safe

Lol, excellent points.

I always like to play devil's advocate, and a huge pet peeve of mine is "we do it this way because we always have" or "we do it this way because that one thing happened that one time". It seems to me like 4 pt harnesses may be a victim of that mentality to a certain extent, but there is no contradicting your points.

Safety should trump all, because no one cares how cool you looked when you got into that crash that widowed your wife and orphaned your kids.

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[Stl-986]

In the end the sanctioning body is going to have a say in what they will allow or not allow. For street legal local laws will dictate. Of course you could remove whatever you put in before an inspection but if you get pulled over there might be an issue. Some DE events will leave it up to you unless they think what you have is unsafe but remember whatever you have for the drive you must also have for the pass if having an instructor with you.

Once you get to the level of a different harness you will be a whole new ballgame which will most likely move you up to a roll cage and a hard top.

[itsnotanova]

I have a friend who got a ticket because he was using his racing harness and not the factory three point. I'm not sure what would happen if he tried taking it to court but something to think about.

[Quadcammer]

Originally Posted by ike84

I certainly cannot dispute any of the points made there. I think it's a really interesting topic to learn about.

There are some good sources that strongly disagree with these points though. For example, a study done by the sae showed v type 4 point harness to be as safe if not more safe than 3 pt harnesses with no occurrence of submarining in their tests. This study assists limited though as the test numbers were small and the crash scenario was quite limited.

https://www.sae.org/publications/technical-papers/content/2003-22-0017/

And schroths crash test videos with the 4pt ASM belt are impressive to watch (although I always question when a company does research that so strongly supports it's own claims)

https://m.youtube.com/watch?v=EGrhJTSQRkY

Anyway, thanks for the replies. It's always nice to hear other people's insights and feedback.

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If you watch the ASM video, look at the dummy's neck at the 1:20 mark. Thats why a 4pt (or 5/6) with no hans is no bueno

[ike84]

Originally Posted by itsnotanova

I have a friend who got a ticket because he was using his racing harness and not the factory three point. I'm not sure what would happen if he tried taking it to court but something to think about.

The schroth 4 pt asm harnesses are actually dot approved and come in street legal versions. The difference, interestingly, is the buckle - racing versions have camlock or latch, street versions have a standard "clip" with the red button. So, if your friend had a camlock or latch harness on I don't think he would get away with it. If it was the dot approved ASM schroth with the little red button, I would go speak to the county attorney (it would then likely get thrown out before even going to court because no one wants a member of local law enforcement to be proven deficient in their knowledge in such a public fashion)

I think it's interesting that every child seat I've ever seen (I'm talking ages 0m - 40lbs) has a 5 point harness. Obviously no hans device with those. Infants that size have a disproportionately large head compared to their body size, and their neck muscles are horribly weak overall. Yet we don't make a big deal over that? However, I have seen (tragically) one trauma case personally of a young kid with atlanto-occipital dissociation (that's what killed Earnhardt, essentially the back portion of the skull - the occiput- breaks its attachments from the portion of the first cervical vertebrae that it normally pivots around - the atlas) who was appropriately restrained in a booster seat with an OEM 3 pt seatbelt. I have also seen an adult in a high speed mvc who was restrained an OEM 3 pt belt who suffered the same fate.

Another interesting thing that isn't talked much about but to me is equally scary is the thoracic (chest) trauma. Multiple papers have shown increased thoracic trauma in 3 pt restraints than restraint systems that include dual shoulder harnesses and avoid the central part of the chest. It's simply a matter of the force being spread out among two belts instead of one and also the belts being positioned away from the center of the chest. No matter what restraint system is used though, ultra rapid deceleration will kill you (that's what happens in a fall!). One of the most mind blowing things I've ever seen was a traumatic transection of the aortic arch in restrained driver who hit a concrete barricade head on at 80mph. To make a really graphic story short, we found that heart heart literally ripped off of her aorta (the major artery that comes out of the heart to supply blood to the entire body). No seat belt, airbag, safety harness, or roll cage will ever prevent that from happening.

Another interesting thing I came across in the ase database are papers about submarining for rear passengers. The short version is that the rear seat used to be considered "safe" because of how badly injured front seat others were, but as seatbelts have evolved over the last 20 years to include pretensioners, spring back mechanisms, etc (none of which, btw, are in our car) it turns out that the back seat is far more dangerous, even for adults, and that submarining with a 3 pt seatbelt is a very real phenomenon. Front seat passengers also can submarine with a 3 pt, which is why the underside of dashes are padded and newer airbags fill that space also.

I tried to dig further into the ase database to learn about 3 pt vs 4 pt vs 5/6/6+ pt harnesses and surprisingly there were only 4 published. The one I referenced, a sister article published 3 years later looking at farside impacts, and then 2 more that were 40+ years old. I didn't see any papers that reference 5/6/6+ point harnesses. I've tried to find other sources of primary literature that addresses this topic but to no avail.

To sum up what I have ready over the past 3 nights - seatbelts save lives, but as is always preached, it is the "system" that matters. Modern front seat passenger systems are the best for street driving, hands down, and race systems such as those found in nascar are best for ultra high speed driving. Nothing is perfect though, and everything else is a compromise of some sort. Ultimately it is up to us as the driver's to understand the risks of what we are doing and those social with our running gear. I do wish there was more primary research to validate common practice and to provide objective data, but (unfortunately) the bottom line is that consumers don't want any more belts to fiddle with and racers don't want any fewer belts to keep their ass in the seat. Except the ricers....(just kidding, sorta).

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[Burg Boxster]

From Quadcammer, STL-986, and intsanova... simply I say this:

You are the epitome of why rest of of hate dealing with trolls like u. We were or rather are genuinely trying to help people like u on this forum but u ruin it for us

You are a big friggin troll. Do whatever you want. If you think your head is only worth $150 then by all means buy a helmet worth $150.

Soyanora

Originally Posted by ike84

The schroth 4 pt asm harnesses are actually dot approved and come in street legal versions. The difference, interestingly, is the buckle - racing versions have camlock or latch, street versions have a standard "clip" with the red button. So, if your friend had a camlock or latch harness on I don't think he would get away with it. If it was the dot approved ASM schroth with the little red button, I would go speak to the county attorney (it would then likely get thrown out before even going to court because no one wants a member of local law enforcement to be proven deficient in their knowledge in such a public fashion)

I think it's interesting that every child seat I've ever seen (I'm talking ages 0m - 40lbs) has a 5 point harness. Obviously no hans device with those. Infants that size have a disproportionately large head compared to their body size, and their neck muscles are horribly weak overall. Yet we don't make a big deal over that? However, I have seen (tragically) one trauma case personally of a young kid with atlanto-occipital dissociation (that's what killed Earnhardt, essentially the back portion of the skull - the occiput- breaks its attachments from the portion of the first cervical vertebrae that it normally pivots around - the atlas) who was appropriately restrained in a booster seat with an OEM 3 pt seatbelt. I have also seen an adult in a high speed mvc who was restrained an OEM 3 pt belt who suffered the same fate.

Another interesting thing that isn't talked much about but to me is equally scary is the thoracic (chest) trauma. Multiple papers have shown increased thoracic trauma in 3 pt restraints than restraint systems that include dual shoulder harnesses and avoid the central part of the chest. It's simply a matter of the force being spread out among two belts instead of one and also the belts being positioned away from the center of the chest. No matter what restraint system is used though, ultra rapid deceleration will kill you (that's what happens in a fall!). One of the most mind blowing things I've ever seen was a traumatic transection of the aortic arch in restrained driver who hit a concrete barricade head on at 80mph. To make a really graphic story short, we found that heart heart literally ripped off of her aorta (the major artery that comes out of the heart to supply blood to the entire body). No seat belt, airbag, safety harness, or roll cage will ever prevent that from happening.

Another interesting thing I came across in the ase database are papers about submarining for rear passengers. The short version is that the rear seat used to be considered "safe" because of how badly injured front seat others were, but as seatbelts have evolved over the last 20 years to include pretensioners, spring back mechanisms, etc (none of which, btw, are in our car) it turns out that the back seat is far more dangerous, even for adults, and that submarining with a 3 pt seatbelt is a very real phenomenon. Front seat passengers also can submarine with a 3 pt, which is why the underside of dashes are padded and newer airbags fill that space also.

I tried to dig further into the ase database to learn about 3 pt vs 4 pt vs 5/6/6+ pt harnesses and surprisingly there were only 4 published. The one I referenced, a sister article published 3 years later looking at farside impacts, and then 2 more that were 40+ years old. I didn't see any papers that reference 5/6/6+ point harnesses. I've tried to find other sources of primary literature that addresses this topic but to no avail.

To sum up what I have ready over the past 3 nights - seatbelts save lives, but as is always preached, it is the "system" that matters. Modern front seat passenger systems are the best for street driving, hands down, and race systems such as those found in nascar are best for ultra high speed driving. Nothing is perfect though, and everything else is a compromise of some sort. Ultimately it is up to us as the driver's to understand the risks of what we are doing and those social with our running gear. I do wish there was more primary research to validate common practice and to provide objective data, but (unfortunately) the bottom line is that consumers don't want any more belts to fiddle with and racers don't want any fewer belts to keep their ass in the seat. Except the ricers....(just kidding, sorta).

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[ike84]

Burg, I'm not trying to troll anyone. I genuinely respect a lot of guys on this forum (including all 3 that you are speaking for) and I try to be an active and helpful participant when I can. The point of my posts is to share information and generate discussion. I'm not arguing for or against anyone or anything (except the fact that safety trumps all, which I've said several times now). If that message got lost along the way I'm sorry. If I seem to be pontificating, that certainly is not my objective. If you simply don't like someone questioning dogma, or citing experiential knowledge and primary data that run counter to it, then I have no apology for you. In the words of Billy Madison "I'm here to learn, everybody, not make out with you!"

Hopefully we're still cool.

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[Stl-986]

Talk about a Troll !

Ike - Dont apologize. Your questions, while sometimes seem strange, are really just questions and you are thinking & questioning. Haven't seen anything in this thread or your others where I thought you were coming across negatively.

Keep on questioning....how else are you or anyone else going to learn?

[ike84]

Originally Posted by Stl-986

Talk about a Troll !

Ike - Dont apologize. Your questions, while sometimes seem strange, are really just questions and you are thinking & questioning. Haven't seen anything in this thread or your others where I thought you were coming across negatively.

Keep on questioning....how else are you or anyone else going to learn?

Thanks dude. I know my brain is wired a bit screwy and my train of thought can follow that. It's kinda like Eminem said in "legacy" lol

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[ike84]

On a related note -

For 5/6 point harnesses, I've read that lap belt adjustment can be a pain and that the "pull up" style is easier. However, for the chest straps, I've read that the "pull down" style is easier. Is this generally true? Can you buy a pull down style harness and convert the lap belts to pull up? I think I've seen 1 or 2 systems that mixes them to get the "best of both worlds" but it's uncommon.

Edit - looks like some specific harnesses are actually designed as convertible pu/pd so I'm guessing that you can't do that with every system

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[Newsguy]

Ike, when I ordered the harness for my dirt track car, pull-up or -down was an option. Having experience previously, I went for the pull-down as pull-up seems easier, but not when down in the car.
On a more global view, it is sad we are saddled with airbags and silly three-point systems. It just illustrates that while pols and bureaucrats feel the need to "protect" us at all times, they were too fearful of backlash to require a superior system.
I will say, having been hit from the side in my A4 (which totaled it,) I had no impact with the side window due to the intervention of the side curtain air bag. The only downside was hitting my wife's head since hers was moving left from the impact. We only had a few stitches, though. Much better than smashing against a window!

[Starter986]

Quadcammer, STL-986, and intsanova

Three of this forums coolest... IMHO

Burg... you've been here a while... what did you "read" that I missed? I've been known to be troll-y so, when I saw those member's names I was, "Uhhhh.... he's never heard of me?".

I've been following the thread and everything I've read, from all participants, seems straight up. Maybe I just don't recognize trolling (I'm serious), or you can spot it a mile away.

Have a great day, Burg.

[Stl-986]

Yea....why wasn't starter included???? lol

with only 5 original posts of his own & 1600+ posts of other threads makes ya kind of wonder who the troll really is.

Anyway...back to topic

[ike84]

Hah! Starter, nice to have you on board !

For me, the real problem is this. I simply don't trust the seat belt in this car. Call me crazy but here's why...

The belts are 20 years old. The common argument that oem seatbelts live forever because they don't get exposed to the sun just doesn't apply. Show me a boxster that doesn't have a faded red buckle latch from uv radiation. Btw, if that plastic is faded, it's structural integrity is compromised.

The latch is bolted to the rail - yes, it's not unheard of. But no sanctioning body in racing is ok with this setup (except if the manufacturer did it!). I get the reasoning - the cars went through crash tests. But its just not kosher in mind. Especially when considering that....

The hardware is crap! I haven't disassembled the belt winder or outboard anchor yet, but the seat rail bolts aren't high grade. Off the top of my head (and I could definitely be wrong) I don't remember seeing any markings on these or the bolt that holds the buckle to the rails. This means that either they are standard grade or made in house (which I highly doubt). I was blown away to not see a 12.9 stamped on those bolts.

Let's face it. If we made this system, no racing body would let us run it. They do though since Porsche passed the crash tests, but the scope of those tests did not necessarily silly to how these cars are driven (on and off the street)

So what is the best (safest) thing to do here for a street legal setup? New belts and receptacles from porsche every few years ($800 for both sides) and replace all the stock bolts with metric 12.9s? Not even possible for the seat brackets unless you tap new threads.

Let's not fall to mention the fact that the airbag system in our cars should be considered "dated" at the least by today's standards

Or you can ditch all of this and go with a street legal 4 point ASM belt but with very little objective data to support superiority (or even efficacy) to 3 point belts and all the questions of submarining and neck injuries that go along with them.

I just don't know the right answer here, and I ****************ing hate not knowing....


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