Some great safety info

[Mac Attack]

Dave I brought up this thread to have a dialog and give information. Why are you being sarcastic with me? I never said people should drive with helmets and harnesses on the street. I asked if it was legal if someone did.

The point of this post was that we maligned a lot of guys for not having a rollbar but having a harness, but the stats here prove they were better off in MOST situations. You bring up the fact that this was in 2002 and that since then we have side airbags but that is not really relavent since no NSX has side bags or curtain bags.

Despite what you said earlier that my post made absolutely no sense to you, there was no sarcasm in mine (hence the lack of the "rolls eyes" emoticon). If your freedom of vision (especially peripheral) was maintained with a helmet and head/neck restraint system, then wearing it on the street would make it a little safer if you were involved in an accident, IMO. Of course, then you get into debates on open face and closed face helmets being safer in the event of a front airbag impact, etc. I'm just bringing this up what you had said before as you're obviously a safety-minded guy. That's a good thing.

I'm stating what I had before as I'm just trying to help inform folks on not only the NSX, but other vehicles. If stuntman disagrees with what I said, fine. He has no formal experience or professional engagement in factory OEM street car restraint theory, design, or testing. Others here do :smile: Now, for a race car where he spends most of his time, then yes, his experience and wisdom should be heeded. But as the advice in this forum would also mostly be applied on the street, then the driver should be aware of the negative impacts, especially if they've removed the OEM airbag.

FYI - yes our airbags are old technology, but they should still work fine in the event of a collision. There's really no set lifetime on this vintage.

I've given my opinion on what I would do on the street and on the track. My hope is to just help inform others and give them ideas of other things maybe they hadn't thought of.

But, today I just dropped my 5YO daughter off for kindergarten in my daily beaten '92 NSX. It has no passenger-side airbag, no TCS, and no ABS. You must calculate your own risks and take responsibility for any actions you've made accordingly.

My $0.02.

Dave

 

[TURBO2GO]

Dave assuming you are correct and the extra travel is good, then how do you explain seatbelt pre-tensioners? It seems to go against what you are saying. Pre-tensioners are specifically designed to anticipate an impact and tighten AS SOON AS POSSIBLE. That's what a harness does. It seems the manufaturers still see that as safer even with no neck restraint.

 

[docjohn]

thank goodness i am happy running with my choice of safety/track gear....if I were on the fence it could be quite a deterent to taking a street car on track.:wink:

 

[Mac Attack]

Dave assuming you are correct and the extra travel is good, then how do you explain seatbelt pre-tensioners? It seems to go against what you are saying. Pre-tensioners are specifically designed to anticipate an impact and tighten AS SOON AS POSSIBLE. That's what a harness does. It seems the manufaturers still see that as safer even with no neck restraint.

Now, the older inertial reel type tensioners we have on our cars does allow for some initial slack before the lock up. Slack isn't necessarily bad, as long as it doesn't let the torso/head move so far out of place where it could contact something it shouldn't, or where the airbag doesn't do a very good job protecting you (and that's why airbags have gotten wider too).

Now, the pretensioners on the newer upper-end autos eliminate that initial slack to keep your torso a little better positioned. The upper torso, however, will still pivot forward, and the belts will still stretch. So, it doesn't go against anything I've said previously, it's just another nice safety feature, like the active head rests, etc. All this technology still relies on having an airbag to cushion your head in a frontal collision. Race cars don't have airbags, and HPDE/track cars remove them for looks, steering feel, whatever. In those cases though, you should wear some supplemental head/neck restraint to give you back the safety of an airbag.

To combat the inertial tensioners on our cars during track use (and what I do for my daughters when they're riding with me in their carseats), usually folks will slide the seat back a bit, buckle up, then jerk the belt and maintain tension to engage the inertial lock. Then, slide the seat forward to maintain the lock when you go on the track. This keeps you restrained a little better.

Look, I've basically gutted my car and started tearing it up after the market on these crashed. Doing whatever I've wanted to it. I removed the TCS (no real danger there as this old system could cause an accident in some scenarios IMO), removed the ABS (there are benefits to keeping it, but previous experiences haved proved I'm comfortable in my non-ABS braking abilities), but I will not change my seats, restraint system, or steering wheel until I make this a dedicated track car.

Dave

 

[stuntman]

I never said "slack" as you stuntman - there is a difference between slack and a more controlled stretch over the short time when you started decellerating. With a 3pt OEM belt, limited pivoting of the upper torso combined with the substantial OEM belt stretch is not slack.

Now, the older inertial reel type tensioners we have on our cars does allow for some initial slack before the lock up. Slack isn't necessarily bad, as long as it doesn't let the torso/head move so far out of place where it could contact something it shouldn't, or where the airbag doesn't do a very good job protecting you (and that's why airbags have gotten wider too).

To combat the inertial tensioners on our cars during track use (and what I do for my daughters when they're riding with me in their carseats), usually folks will slide the seat back a bit, buckle up, then jerk the belt and maintain tension to engage the inertial lock. Then, slide the seat forward to maintain the lock when you go on the track. This keeps you restrained a little better.

Sounds like you have changed your mind about the majority of 3-pt belts having unwanted "slack". Pre-locking a 3-pt belt does maintain pre-tension the same way a 4pt harness would, but with a 4-pt having more surface area to distribute the impact/load across your body evenly compared to the diagonal 3pt harness which could also be in a less than ideal location at the base of your neck.

Pre-locking a 3-pt belt does not allow the majority of the 'slack' to 'cushion' the impact and allow the airbag to do the majority of the deceleration of your head (which is more like a punch in the face with many broken noses and injuries from the airbag itself).

While belts do stretch i'm not sure I would agree that there is substantially more 'stretch' of an OEM belt over a racing harness to cushion the impact better. I still would have to say that the tighter the belts are initially (just like you stated by pre-locking the 3pt belt) is safer and reduces injury.


The topic of whether a harness and or rollbar, hans device and when to be used, etc... will always be debated and many will hold tightly to their beliefs and opinions. And you know what they say about opinions...

There is a decent amount of info here as well as many other threads and web site debates on what is better but at the end of the day it's up to the individual to decide what is best.

 

[Mac Attack]

I haven't changed my mind about slack. I was never talking about slack in my posts until you brought it up. As I explained before, there is a difference between slack (which doesn't control or reduce your acceleration) versus belt stretching and resistance and slower deceleration of your head due to your upper torso pivoting and slowing from the 3pt arrangement.

Now, the reason some people with OEM belts take up the initial slack before they head out on the track is to hold them more firmly to the seat during cornering. Even the nice side bolsters in the NSX still allow for some sliding around. Do all the NSX's you've been in on the track have aftermarket restraints? If not, you should try the inertial reel trick next time to lock you into the seats better (as opposed for just the safety aspect).

I personally do it in my car for my little girls car seats since the NSX obviously doesn't have the LATCH system. I think it's a safer arrangement but it may not make any difference. I don't do this for myself.

Oh, I've never heard of the 3pt arrangement (with only one belt diagonal across your torso) crushing anyone's chest during any accident. That refutes the idea that a 4pt is better in the real world for street applications(although it theoretically is). You typically only worry when the head is whiplashed (hence the airbag or a head/neck restraint).

Dave :smile:

 

[stuntman]

Even the nice side bolsters in the NSX still allow for some sliding around. Do all the NSX's you've been in on the track have aftermarket restraints? If not, you should try the inertial reel trick next time to lock you into the seats better (as opposed for just the safety aspect).

I've driven over 15 different NSXs, over half of them were on track, and only 3 had harnesses (Harness/Seat/Cage, Harness/Seat, and Harness/STOCK seat). I've tracked a lot of stock cars and everything in between as well and am familiar with the pre-tension trick.

Oh, I've never heard of the 3pt arrangement (with only one belt diagonal across your torso) crushing anyone's chest during any accident. That refutes the idea that a 4pt is better in the real world for street applications(although it theoretically is). You typically only worry when the head is whiplashed (hence the airbag or a head/neck restraint).

Dave :smile:

I never said a 3-pt belt 'crushed' anyone's chest, but simply stated that a 4pt harness has more surface area than a 3pt -which distributes an impact over a greater surface on the body, reducing injury. 3pt belts have caused minor injuries including improper fitting and the diagonal belt crossing the neck and not the shoulder, resulting in more injuries. These are minor compared to not wearing a belt atall, but they are further examples of a 4pt harness' advantages over a 3pt.

Having been in crashes both on and off the track in both 3pt and 4pt harnesses (also both in stock seats as well as race seats) I will take a 4pt harness over a 3pt any day.

You have logical points and your own opinion. I respect that and am not trying to force my opinion or experiences on you by any means. A lot is lost through miscommunication through text and I don't really have anything further to add nor want to create any controversy.


billy

 

[TURBO2GO]

Listen to what it says at the 2:00 minute mark:


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[TURBO2GO]

This video shows a side by side of a harness versus a seatbelt. They are timed the same. The crash takes place at the same point. Looks a lot like the 3 point and its extra travel puts MUCH MORE pressure on the neck/head. The opposite of what we have been assuming. I'm not stating this as fact, just saying it sure looks that way on the video.

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[stuntman]

I guess I will add 1 more thing:

Whether you're wearing a 5-6pt harness or (especially) a 4pt. It's important to tighten the lap belt FIRST as tight as you possibly can before tightening the shoulder belt. You want the buckle low across your lap for this very reason. I often see many 4-5-6pt harnesses worn improperly with the buckle as high as the middle of the chest. Keep the buckle low.


Billy

 

[Mac Attack]

This video shows a side by side of a harness versus a seatbelt. They are timed the same. The crash takes place at the same point. Looks a lot like the 3 point and its extra travel puts MUCH MORE pressure on the neck/head. The opposite of what we have been assuming. I'm not stating this as fact, just saying it sure looks that way on the video.

That's a good video showing the differences, but like any propaganda, can be made to show whatever point I wanted to prove.

Where to begin critiquing it?

Seat design: Obviously, the seats in the video are of two completely different designs. Seats play an integral role when Honda crash-tested our cars. The seats, belts, and airbag all work together harmoniously to protect us. That's why I cringe when folks put cheap asian knock-off seats in their vehicles that haven't been tested, other than to have the fake carbon weave look straight.

Seat position: Did you notice how the seat with the 3pt belt was inclined further back than the 4pt harness? That allowed the dummy to slide down in the seat and their head to contact the diagonal belt, resulting in a lot more movement. Inclining the seats back unnecessarily (i.e. to have the gangsta look) is another extremely dumb thing to do in your car. Of course you're going to slide under the belt (and a 4pt won't help you with that either unless you do what Billy said and tighten the belt properly). The slight extra seat inclining and the increased submarining due to that made the biggest difference in whiplash in those videos. Kinda misleading, eh?

These kinda minute differences to the untrained eye (no offense, we're here to help educate each other) make a world of difference in what you see in videos and the real world. Obviously Schroth is trying to sell their products, but take it with a grain of salt.

I still stand by my experience. I have not given any opinions here without good justification to back it up.

Make your own informed choices and try to be safe!

Dave

 

[TURBO2GO]

What I'm seeing is an incredible amount of "give" even in the harness. The idea that you are strapped in rock solid and the body does not move and the head does; versus the lap belt, isn't all that correct. The lap belt is just allowing for MORE movement, but there is certainly quite a bit with the harness too. These crash test videos are enlightening, I mean just look at how much the body is moving around.... it's crazy...

And it isn't just the initial impact, it's the "rebound" that is just as bad... teh body is shaken, not just thrust forward. Look at this corolla video, you can see the dummy head travel ALL THE WAY to the steering wheel, then rebound, bounce back, EXIT THE WINDOW, and hit the pillar post of the car!!!

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[TURBO2GO]

Has anyone ever seen/used the Isaac? Looks pretty interesting, it is actually using mini shock absorbers for your head:

Here is a good page that has all the head/neck restrains listed and explained:

http://www.trackpedia.com/wiki/Head_and_Neck_Restraints

 

[Mac Attack]

You typically only worry when the head is whiplashed (hence the airbag or a head/neck restraint).

Slack isn't necessarily bad, as long as it doesn't let the torso/head move so far out of place where it could contact something it shouldn't, or where the airbag doesn't do a very good job protecting you (and that's why airbags have gotten wider too).

I removed the TCS (no real danger there as this old system could cause an accident in some scenarios IMO), removed the ABS (there are benefits to keeping it, but previous experiences haved proved I'm comfortable in my non-ABS braking abilities), but I will not change my seats, restraint system, or steering wheel until I make this a dedicated track car.

Yup, it's mostly about head/neck restraint.

 

[TURBO2GO]

When I was buying a helmet I tried many different ones, eventually spent $1000 on an Arai. All sorts of things were mentioned to me, but what no one mentioned is that the weight of the helmet is not just something that affects comfort. Having a heavier "head" creates more inertia in an accident. That extra few grams will add to the force that your neck has to deal with.

 

[docjohn]

So Dave after all this time on prime it seems like your educating yourself and becoming very interested in safety,good for you,I like to see guys get passionate about a specific facet of nsx ownership and teaching the rest of us...Seems like Mac also has some solid background in the matter,and of course Billy who seems to have some realworld experience ..dare I call him our resident crash-test-du...y:biggrin:

 

[Mac Attack]

Darn you turbo for linking crash-test videos! Those things are so addictive - I've been looking at all kinds of cars on youtube :biggrin:

Dave

 

[TURBO2GO]

Yeah I don't know Doc, I find myself looking at hours of video and reading tons of material on this. Maybe it's because I'm old... lol... you get safety concious when you get old.

I mean a few months ago an instructor with the PCA died. He had a family. That guy isn't coming back. I was talking to a guy that builds cages and he kept saying XYZ guy at XYZ event, yeah that guy was "de-gloved" and Joe shmoe last year at blah blah, he was "de-gloved".

"de-gloved"??? LOL... I was thinking "get me a window net, NOW"

 

[docjohn]

there is alot of hpde lore/gore stories that get multiplied/blown up ect...but people do get killed at track events and do get hurt.Heck a budy of mine t-boned and totaled his 996 tt years ago at a friggen auto-x,and had to get a ct scan for belly/chest pain.As always we have to participate with at least the minimum of safety to satisfy the event organizers/track...where each of us goes from there is up to the individual.

 

[ryneen]

On the subject of safety, I bought a Comptech harness bar and 4pt harness. I'm also getting a Sparco Evo seat.

I purchased the Science of Speed sliding seat rail and noticed that the steel slots to mount the seat don't look sturdy enough to hold the seat in place during a serious accident. Does anyone have any insight into whether the seat rail is sturdy enough to mount the seat? If not, I'm assuming I'll need to order a fixed Sparco mount instead.

Image: http://www.scienceofspeed.com/produ...ing/sliding_seat_mount/seatmountNSX-R_800.jpg

 

[TURBO2GO]

On the subject of safety, I bought a Comptech harness bar and 4pt harness. I'm also getting a Sparco Evo seat.

I purchased the Science of Speed sliding seat rail and noticed that the steel slots to mount the seat don't look sturdy enough to hold the seat in place during a serious accident. Does anyone have any insight into whether the seat rail is sturdy enough to mount the seat? If not, I'm assuming I'll need to order a fixed Sparco mount instead.

Image: http://www.scienceofspeed.com/produ...ing/sliding_seat_mount/seatmountNSX-R_800.jpg

I don't know the facts about that rail but judging by looks alone.... there is NO WAY that I would put myself in that rail. If the seat comes loose then you have some REAL problems. It's bad enough that harness bar can come loose.