Seatbelt bar

[doorpz]

I was just curious if anyone knows some place where i can get a pre made bolt in seatbelt bar for a 74 beetle. i'm not looking for a whole roll cage just the bar that goes behind the seats to attach a 4 point harness to. thanks.

[ericsbracer]

I would not recommend mounting a bar to the door posts. It just wouldn't have the strength to protect you in a frontal impact (and I know about frontal impacts). If you don't want a full cage, look at the bolt in roll bar available at http://www.ronlummusracing.com/rlr2/Race_store.htm and check out the chassis and Roll cage section. That would give you something substantial to mount your shoulder harness's to, and not be very intrusive.

[doorpz]

i wasn't really planning on going with a roll cage but i guess it can't really hurt anything. i don't really like the bar across the drivers door but i'm not really planning on this to ever be a daily driver so i guess its not really a big deal. well i guess now i have to decide whether i want to drop the extra dough or not. thanks for the link.

[Aurumen]

You can also get floor mounted belts and mount them to the rear seat belt bolts. That's what I currently have and it seems to work pretty well. But I don't road race my car at this point, only autocross. For road racing you should really have a roll bar at the very least.

[doorpz]

yeah i guess i could do that. i just finished make some back seat delete panels but i guess i could just cut some holes where the seat belts would mount. i'm not really worried about the passenger seat so much just the drivers side. i don't think i'll ever end up road racing it but it will probably see a little auto-x action. i'd like to get a roll cage but the money is a little tight right now getting the rest of the car together so i think i'm going to hold off for now. on a side note who makes a good 4 point harness? i've sort of looked around but there is so many i'm not sure which ones are quality and which ones kids put in their civics. thanks.

[Jake Replies]

I was just curious if anyone knows some place where i can get a pre made bolt in seatbelt bar for a 74 beetle. i'm not looking for a whole roll cage just the bar that goes behind the seats to attach a 4 point harness to. thanks.

I am looking to do the same thing. I have a few Autocross friends that have a set up like this so they can us a 4 point harness to help keep them in the seat. I currently just have a lap belt, and I have to tighten it down so it pins me to the seat so I do not slide around while cornering, but a 4 point "tuner" harness would work better.

I have a 1962 Beetle with full interior. I would like to find a way to mount a bar between the 2 upper seatbelt bolts on the pillars and wrap the tops of the 4 point harness to it. I DO NOT want a roll cage, and I do not even plan on leaving the bolt in bar in the car for anything other than autocross. Bolting the tops of the harness on the back seat belt holes is a good idea too, but I wonder how that would worth with a stock seat still back there, that and think the bar might help with flex of the cars chassis too.

What every I do, I have to figure it out by December for a race. I was looking into the Sparco Harness Bars, but they only make them for the more popular sports compacts. I was thinking maybe one of those bars can be make to work with a Bug too. I will have to see what are the dimension. I was thinking of using the bar with the Sparco "Tuner" Harness or the similar G-Force Harness, but whatever I use, the Sparco Harness Bars are not cheap.

Here is a link:

http://www.sparcousa.com/harness_bars.asp

Let us know what you ended up doing, and I wil try to do the same if I do something different. Good luck.

[Aurumen]

yeah i guess i could do that. i just finished make some back seat delete panels but i guess i could just cut some holes where the seat belts would mount. i'm not really worried about the passenger seat so much just the drivers side. i don't think i'll ever end up road racing it but it will probably see a little auto-x action. i'd like to get a roll cage but the money is a little tight right now getting the rest of the car together so i think i'm going to hold off for now. on a side note who makes a good 4 point harness? i've sort of looked around but there is so many i'm not sure which ones are quality and which ones kids put in their civics. thanks.

Just be very careful wearing a 4 point harnass on the street or in road racing without a roll bar (or cage). I went to a road race a few years ago and a guy in a Neon rolled his car with a belt on. He was wearing a 4 point harnass and the roof collapsed on to his helmet. With the 4 point harnass on, his shoulders couldn't move so when the roof collapsed on him his head was pushed sideways. Luckily for him the roof didn't collapse too much, because if it had collaped just a few more inches it would have snapped his neck. With standard seat belts, when the roof collapses, your whole body gets pushed to the side. But with the 4 points, your head is the only point that can give. I have both the 4 point harnass and standard seat belts installed and use the regular seat belt to and from events.

Oh and remember when you slide off the course into the grass, drive straight! The guy in the neon tried to correct at high speed in the soft grass and his wheels dug in!

Nick

[ericsbracer]

There's a reason why most, if not all, racing orgs mandate both the rollbar and the shoulder harness bar. The rollbar speaks for itself - if you go over, the roof will collapse...

The shoulder harness isn't so obvious, but just as important. Belts, All Belts, will stretch around 15-20% in a moderate to serious frontal impact - this is a figure I've heard from Simpson and Autopower people. Now - think about how much longer you're shoulder belts are if they have to run from the buckle All the way over the seat and down to the floor (or back to the rear deck). That's another 24 inches of belt(approx) and 4-5 inches of stretch.. do you want to get that much closer to your steering wheel? Another problem, if the belts are mounted as you suggest-to the lap belt mounts-the angle over the shoulder is wrong, and you're upper body could cantilever at the waste - especially if your seats tilt forward like stockers do. All the approved belt manufacturers have very specific installation instructions - which should be followed to the letter... this is a long load(3MB), but worth it..

http://www.simpsonraceproducts.com/medi ... st9-03.pdf
This is a little more on the restraints:
http://www.simpsonraceproducts.com/safe ... raint_info

I have a great deal of knowledge in frontal impacts, and how these things are supposed to work. Here's how I learned... http://www.superbeetlesonly.com/forum/i ... si&img=806

[doorpz]

I have a great deal of knowledge in frontal impacts, and how these things are supposed to work.

That looks pretty wicked man hope you were okay. What kind of speeds were you doing when that happened? Pictures like that is what makes me want to upgrade my seatbelts and stuff. For the time being though i'll probably just use the standard belts at least until i get the car up and running again then i'll see about getting a cage and better belts if i have enough money left over.

[ericsbracer]

I suppose that would depend on your definition of "OK"... I had a sternum strap failure, so my sinuses got used for an air bag. A few months of having my jaws wired shut, a couple surgery's, and I'm good as new.. although my face is no longer symetrical

The speed has been estimated somewhere between 45 (the sternum strap manufacturers estimate) and 90 (my tach, RPM, a spreadsheet).

The injuries resulted from me coming out of my shoulder harnesses when the strap broke - but even my lap belts stretched a couple inches..

and yes I sued, and no it wasn't worth it, and NO - I'd Never go through that (the legal part) again..

[WD-40]

Eric-

I respect your opinions on harnesses more than just about anyones, but I have a few questions for you:

1) When you say you do not think the harness bar (shoulder belt mount to shoulder belt mount) would be adequate in a frontal collision, do you mean "It isn't any good", or "It isn't as good as a harness tied to a real cage"?

I can see how the later would be true. However, I also wonder if the harness bar with a proper 4 or 5-point harness could be safer than the stock 3-point belts? (Note that this is for frontal collisions, not a rollover with a crushed roof situation)

2) With regards to the belt stretch- I'm sure you are familiar with Dale Earnhardt's NASCAR accident. The autopsy reports said he died of a "basal skull fracture", as a result of his body being tightly restrained, but the mass of his unrestrained head flying forward. Is there any thought in the racing world that some belt stretch is OK (perhaps even counted on) to give the body a few more inches to decellerate in a collision?

(This is of course with the assumption that the average racer with a harness bar is NOT going to be using a HANS device of any sort.) So in our case, the 4-5 inches that the rear-mounted belts would stretch... if this 5 inches still kept the driver's head away from the steering wheel, wouldn't it be OK, and perhaps even beneficial? The harness bar would still be required as a guide-only for the straps (to keep spinal compression from being a problem).

- David

[ericsbracer]

Eric-

I respect your opinions on harnesses more than just about anyones, but I have a few questions for you:

1) When you say you do not think the harness bar (shoulder belt mount to shoulder belt mount) would be adequate in a frontal collision, do you mean "It isn't any good", or "It isn't as good as a harness tied to a real cage"? I can see how the later would be true. However, I also wonder if the harness bar with a proper 4 or 5-point harness could be safer than the stock 3-point belts? (Note that this is for frontal collisions, not a rollover with a crushed roof situation) I think the bar, or more to the point, a bar mounted to the door posts, wouldn't be strong enough to sustain the "G" forces your body creates in a reasonable front end impact. Better than a 3 point? Maybe, but certainly a poor substitute for a proper roll bar with the madatory diagonal and shoulder harness bar.

2) With regards to the belt stretch- I'm sure you are familiar with Dale Earnhardt's NASCAR accident. The autopsy reports said he died of a "basal skull fracture", as a result of his body being tightly restrained, but the mass of his unrestrained head flying forward. Is there any thought in the racing world that some belt stretch is OK (perhaps even counted on) to give the body a few more inches to decellerate in a collision? Very familiar - and Simpson contends (and NO One, Not Even NASCAR proved him wrong) that the belts were mounted improperly and, due to that, tore leaving him free to move forward. Some stretch is expected, and probably for the reason you mentioned, but belt length plays a key roll. Also - the stretch is based on the assumption the mount will not move, and I'm not sure that's a safe assumption with a door-post mounted bar.

(This is of course with the assumption that the average racer with a harness bar is NOT going to be using a HANS device of any sort.) For what it's worth - most racing organizations have mandated full face helmets and a HANS type of device. At a Minimum, and mostly in vintage orgs, a neck collar must be worn to limit head movement. So in our case, the 4-5 inches that the rear-mounted belts would stretch... if this 5 inches still kept the driver's head away from the steering wheel, wouldn't it be OK, and perhaps even beneficial? The harness bar would still be required as a guide-only for the straps (to keep spinal compression from being a problem). 4-5 inches of stretch would be 'acceptable' - if everything else did it's job properly, depending on the impact. My steering column came in the car over 6 inches - extreme case - yes, but.... My gut feeling is by the time you put that harness bar in, mounted in such a way as to make it strong enough to do it's job - you'd have done more than just putting in the bolt in bar. You don't need the door bars, so interior access isn't comprimised much.

What it comes down to is - what's more important - convenience or saftey? I know it's a cheesy question, but if you're racing, you're taking a serious risk, especially with cars of this age. I can tell you from experience, you don't get "do-overs", and it only takes once to wish you'd done it right the first time.

I really do hate to sound "preachy", but I've met a lot of people who've gone through some serious medical recoveries because they didn't put enough emphasis on safety preparation. It's an easy area to take short cuts on the 'It won't happen to me' justification. It CAN happen, I know, and If it does - can you live with yourself?

- David

[Jake Replies]

I respect your opinions on harnesses more than just about anyones, but I have a few questions for you:

1) When you say you do not think the harness bar (shoulder belt mount to shoulder belt mount) would be adequate in a frontal collision, do you mean "It isn't any good", or "It isn't as good as a harness tied to a real cage"?

I can see how the later would be true. However, I also wonder if the harness bar with a proper 4 or 5-point harness could be safer than the stock 3-point belts? (Note that this is for frontal collisions, not a rollover with a crushed roof situation)

2) With regards to the belt stretch- I'm sure you are familiar with Dale Earnhardt's NASCAR accident. The autopsy reports said he died of a "basal skull fracture", as a result of his body being tightly restrained, but the mass of his unrestrained head flying forward. Is there any thought in the racing world that some belt stretch is OK (perhaps even counted on) to give the body a few more inches to decellerate in a collision?

(This is of course with the assumption that the average racer with a harness bar is NOT going to be using a HANS device of any sort.) So in our case, the 4-5 inches that the rear-mounted belts would stretch... if this 5 inches still kept the driver's head away from the steering wheel, wouldn't it be OK, and perhaps even beneficial? The harness bar would still be required as a guide-only for the straps (to keep spinal compression from being a problem).

- David

Thank you. I was thinking along the same lines, and I too mean no disrespect.

A) A Harness Bar and a Tuner Harness would be better than a stock lap belt for more than just keeping someone in their seat during hard cornering.

B) How severe of a collision would cause a triangulated Harness Bar to fail, or a seat belt to stretch, and would that type of collision ever be seen in a SOLO 2 Autocross event where the only frontal impact comes from a cone.

Eric has some of the greatest experience and advice here, and I mean no disrespect. I am just trying to keep things in context. I drive a low 13-second Bug almost every day, but yet I am required to wear a helmet when running at the track, should I wear the same helmet every day for the same safety reasons too? Things like this make it hard to say.

[ericsbracer]

Thank you. I was thinking along the same lines, and I too mean no disrespect.

A) A Harness Bar and a Tuner Harness would be better than a stock lap belt for more than just keeping someone in their seat during hard cornering.

B) How severe of a collision would cause a triangulated Harness Bar to fail, or a seat belt to stretch, and would that type of collision ever be seen in a SOLO 2 Autocross event where the only frontal impact comes from a cone.

Eric has some of the greatest experience and advice here, and I mean no disrespect. I am just trying to keep things in context. I drive a low 13-second Bug almost every day, but yet I am required to wear a helmet when running at the track, should I wear the same helmet every day for the same safety reasons too? Things like this make it hard to say.

For a SOLO 2 car, I suppose a triangulated harness bar would work. For that matter, if it's properly done, it should work in most situations. I may have misunderstood the original posting-I was under the impression we were considering more of a homebuilt kind of thing. Thing is-if it's triangulated and mounted safely, the interior is compromised just about as much as it would be with the bolt-in roll bar. My bigger concern, and this comes from a lot of experience, is people tend to do safety things once, not progressively as the car developes. So the harness bar is done, then the car is improved, and suddenly the harness bar is of little value, relative to the cars usage and/or performance. (up on the soapbox) I just think that if you're going to do something like that, you might as well do it right the first time (steps down from soapbox).

[WD-40]

Good discussion here.

I think the takeaway message is that accidents can be so different, that the devices that help the most in some cases can also hurt the most in others. The key being, you have to pick the options that can help the most with the least risks of hurting.

I looked up the Earnhardt thing again- it looks like there was a LOT of debate about the harness, and wether it failed or it was improperly installed. But it sounds like the final conclusion from the autopsy was that wether the one harness strap failed or not, he STILL had too much of a differential between the chest and head velocity. So if the harness DID in fact fail (or was improperly installed), he still would have died even if would have remained tight & secure.


I did some more reading, and found some interesting things about the harnesses and harness bars. It's all hit and miss, opinions and facts... but I learned a bit and drew some conclusions that I think make sense. I'll try to sumarize them here.

1) A 4-point harness can cause serious injuries in situations where a factory 3-point belt would be OK. The thing is, in an accident, your shoulders can rotate forward, pulling on the shoulder belts which will pull up on the lap belt. The lap belt then moves from your hips (where your body CAN support the load) to your stomach, where your internal organs are vulnerable. Because of the way that the 3-point anchors in the corner, pulling on the shoulder belt won't move the lap belt. For this reason, 4-point harnesses should be avoided, and either full 5 or 6 point harnesses should be used, or just the stock 3-point belt should be used.

2) A typical "harness bar", when a 4/5/6 point harness is attached, can be deadly in a rollover accident. The logic here is that a factory 3-point allows the upper body to move left to right, whereas a harness securely locates the upper body in an upright position. In a rollover without a cage (where the roof caves in), with a harness bar & harness only, the upper body is stuck upright, and it's your head & neck that must deal with the roof coming at you. With a stock 3-point belt, the whole upper body can move out of the way, greatly reducing the possibility of head/neck injures. Here's some example pictures. The driver and the passenger (instructor) in the BMW walked away without injuries. The driver of the CRX was banged up, but was OK. That's his helmet sticking out the window. In both of these cases, the occupants most likely would have died if they had been wearing a harness instead of the stock belts. (neither car had a roll bar or cage)





3) A harness bar can cause injuries in side impact collisions. What happens here- say we have two occupants, the driver and a passenger. An impact on the driver's side with stock belts would push the pillar in, creating excess slack in the driver's 3-point belt, and no change for the passenger. The same impact with the harnesses located on a harness bar could shift both upper belts, taking the head/neck/upper body of both occupants with them, and potentially tightening the harnesses to a point that could cause harm.


Soo.... this pretty much is a deal breaker for me. Even if you just use a plain bar to avoid the downward spinal compression (with no locating loops or anything else welded to the bar itself) with the harnesses attached to the rear, you still have problems. Yes, the side impact would now be OK, and yes, the frontal collision safety could be improved (positive: load distributed on both shoulders, negative: belt stretch), but it still wouldn't allow enough side to side movement to be of that much benefit. With the rearward mounting, it would have much more side to side freedom than one attached to the bar itself, but it still could only move so far. Only if the harness bar was an arc centered at the lap belt's level could it really rotate much side to side. If you're putting that much effort into it, you might as well build a cage.

After learning this stuff, I can't see how it would be a good idea.
(But, in the spirit of discussion, please chime in if you find something I was wrong on, or if you have other ideas!)

- David