N80

I've heard people criticize harness bars but not sure I remember why. I understand that they do not provide the same level of safety as a roll bar and certainly not a cage. But my interest has more to do with getting some harnesses in the car that will hold me in the seat better than the stock lap belt.

Here is how I see the benefits of a harness bar:

1) Hold driver securely in the seat for better feel and ease of driving....i.e.: it is harder to operate the car when sliding around in the seat.

2) Relatively cheap.

3) Does not require any significant mods.

4) Does not make car less useful as a DD.

So what are the real cons of a harness bar from a safety standpoint or otherwise?

terrasmak

iTrader: (8)

Harness bar is great for autocross but you don't want to be that secure in the car on an open track nor the street. if your roof comes down , the 3 point seat belt will let you move out of the way.

N80

I would be using one for road coarse DE.

Is this a theoretical concern or have there been documented cases of this being an actual cause of injuries?

I wear a G-lock on my lap belt already which means that unless I submarine, my hips are not going to go downward....and if the shoulder harness retracts and holds....which from personal experience they do...I don't think the stock set up affords a great deal of protection from roof collapse either.....but I'm just guessing.

Anyway, I will take note of that as a possible issue and I'll do some research to see if there are actual cases of this being an issue.

I do know that I have ridden with some experienced time trialers in Corvettes that used harness bars.

2000atlanticgt

iTrader: (5)

I have been going back and forth on this as well for the same reason as you. I am convinced the risks of using a harness bar with harnesses holding you up right is a definite increase in risk compared to factory 3 point seat belts in a roll over. I have personally been involved in a rollover accident on the street where the other car's roof directly above the driver was crushed down level to the dash, but the driver survived with minor injuries. If he would have been in a harness holding him upright it would not have been the same outcome. That is the best real life example I have ever experienced personally to relate to this topic.

Now how many HPDE cars have you seen go up side down, and what added saftey do you add by having the driver more secure behind the wheel are both hard to judge.

Then looking at it the other way, what are the cons to having a roll bar in the car you drive on the street? From a saftey standpoint as long as the 4 pt bars are not any closer to you than any of the other sheet metal already in the car I don't see how your adding any risk using the harness or even the factory seat belt on the street. From a safety standpoint, the roll bar still seems like the best option and with safety I don't want to choose the second best option.

N80

In general a roll bar in a street car sounds like a bad idea if there is any way your head can hit it. It would clearly damage your skull more than an a-pillar or b-pillar.

And for the harness bar to be the cause of a roll over head injury it would have to be a very specific type of impact. I have been in a roll over accident in a street vehicle (at least 6 rolls....I was not at fault) and the roof buckled upwards, not inwards. And the shoulder harness held me in place so firmly that it broke my collar bone.

But, I'm looking for more than anecdotes, theoretical concerns or even a rare example. I have not been able to find any actual examples of harness bars being responsible for head or spine injuries related to roof collapse.

And let's say it is a real risk. You still have to weigh it against other benefits the harness bar provides (risk vs benefit). Surely in frontal and side impacts a harness bar with a five point harness would provide some additional benefit over the oem shoulder harness. That type of impact would be a lot more likely than a direct roof top impact. Not to mention the benefit of better car control which is specifically what I'm after.

Anyway, I'll wrestle with the issue for a while and talk with guys at the track too.

SparkleCityHop

iTrader: (30)

Autocross - there should be no risk of rollover, so harness bar alone is ok.

Road course - there is a risk of rollover, and a 3 point belt allows your body to shift if the roof is crushed. A harness without a roll bar keeps you in the upright position and could kill you if the roof is crushed since 1) you have no roll bar to keep the roof from coming down on you and 2) your body has nowhere to go since the harness will hold you in place. If you are road racing, you should have a minimum of a roll bar along with the harness. Otherwise, you are putting yourself at a high risk of paralysis or death in the event of a rollover - arguably higher than if you were just using the 3pt seatbelt.

Also, for street - in many states, using a harness on the street is illegal, because it is actually more dangerous than the 3pt. The harness will not protect you any more in a side collision than your airbags and 3pt that have been designed and tested for those types of impacts. The harness simply keeps you exactly in place. Sometimes that will be to your detriment depending on what happens to the rest of the cabin space.

IMO, the main reason for a harness and a proper racing seat is for you to maintain a good body to car connection so that you can feel the feedback from the vehicle and you can maintain proper body mechanics and control of the car while under different forces. It only becomes a part of a proper safety system when you use it along with the proper roll bar, cage, helmet, padding, etc.

N80

That makes sense, but as mentioned, I've seen no data that confirms that this is a real risk or even that it has ever happened. And as mentioned, even if it is a risk and had happened, not all rollovers result in a collapsed roof. Many result in a 'tented' roof.

I'm not trying to argue. But I've heard this theory before and still never seen any real proof to suggest that it is a 'statistically significant' risk (as they would say in the medical journals). So to say that you are putting yourself at "high risk" seems unlikely. I'm not convinced that the theory is wrong, but I'm not convinced that the fairly remote risk that it represents outweighs the admittedly minimal safety benefits a harness confers without a cage or rollbars.

And as far as I know, harness bars without roll bars are legal on the track in DE and TT, at least with NASA they seem to be (although I'm not real familiar with TT regs).

SparkleCityHop

iTrader: (30)

Sounds like you have made your decision. I don't know that there's anyone out there with emperical data on studies for cars with/without certain safety equipment or impact types - so you're probably not going to get anything other than conjecture.

Just decide what you think is the appropriate amount of safety/risk and within the regulations of your selected race organization.

I lean towards a full cage and harness since mine saved my life, but no one else is going to have the exact same wreck as I did or be in a roadster either.

Jagerz

I had a harness bar and kept the factory 3 point belt installed. Definitely don't use the harness on the street. I weighed the pro's and con's before hand... the harness planted me in the seat better and that extra control made it worth it for me. It made a big difference in my driving.

mhoward1

The issue you are going to find in your justification is an official study being done to build such data. No one will be willing to fund that research since the automakers only car about 3 point setups, the insurance companies don't care since they will not cover it, and none of the harness bar makers have the funding or the will to see actual results. What that leaves you with is looking at the over design of the systems and the possible outcomes of the accident. Any other information posted or said will be nothing more than antidotal without actual data.

A Three point system, even with cam locks and belts locked still drive the occupant down and towards the center of the vehicle in case of any roof intrusion, that is just the way they are designed. Without an exit point then any harness will keep the body, and specifically the head in place at the top of the seat. That becomes an impact point if the roof comes in. SO your options are keep the roof from intrusion, of have an exit point. If you use a 4 point your exit point is in to the foot well, which is a terrible option since that is a crush point on almost all cars. So the only other option is increase roof support.

If this all acceptable risk then go for the harness bar. Heck even doing an HPDE is a risk, so we all weigh our tolerance when we do what we do. I sure cannot talk much, since I run with no top in a race car, but I do have a lot of safety gear, including fire suppression, H&N restraints, and full safety apparel.

N80

Not at all. That's why I'm asking and weighing the options.

But I think Marty has pretty much summed it up. And Marty might know this, but I'm pretty sure several of my instructors were running harness bars in their NASA TT cars, Kim in his Corvette I believe, so I don't think I would be the only one bucking conventional wisdom in this.

Anyway, totally off topic, but Marty, I'm thinking about doing a DE weekend with THSCC in October at Kershaw. Do they run a pretty good show?

KingBaby

iTrader: (3)

Good stuff!

We've seen that the Z is great in street accident situations. I'd say a harness bar is a quick solution to securing the driver. Any driving with high average speeds/heavy door to door road course traffic! Cage no doubt!

mhoward1

First Question,
yes, many of the TT cars run harness bars in NASA. The rules allow it and many people don't want to commit the car to a full roll bar since many require modifying the interior. That doesn't mean it is the corrent choice, or incorrect. It just means that is their threshhold for personal safety. I do question that in a vette especially. The speeds the Z06's run is pretty darn high.

As far as the Tar Heel events, they run a great show. Well organized, plenty of track time, and overall a fun environment. Then again, I am bias.

350Zdj

iTrader: (3)

How about this?: just install a perfectly sized fixed bucket seat and use the OEM 3pt belts with the CG Lock mod. Holds the driver in place very well, while keeping him/her mobile when the roof gets crushed.

betamotorsports

iTrader: (1)

Drive and passenger walked away uninjured from this hard flip. Both were wearing 5 point harnesses and notice the improperly installed roll bar punched through the floor.



IMHO, the issue of getting your head crushed in a rollover because you're wearing a full race harness and the car does not have a roll bar is greatly exaggerated. Its classic example of people exaggerating the risk from rare yet spectacular occurrences.

SE5spd

iTrader: (17)

Why not buy a fixed back seat with stock seat belt, then later get a Kirk 4 pt roll bar and harness?

mhoward1

Remember that the main reasons the Driver and passenger ddn't get hurt was because the builder also used cheap seats that were also improperly installed that broke and flattened with the roof. That was a matter of pure luck than any safety design. It could have gone the "much worse" route too.

N80

Probably my best option. I'm still trying to figure al this out. A lot of variables to consider including cost, safety (making and informed assessment of risk), actual need, actual benefit, minimal mods to the interior and daily driver usage. I know the answer is a dedicated track car but that just isn't in the cards right now.

I've considered a Kirk roll bar but understand it is best not to use them in a street driven car. I'm also remotely interested in working up the ladder to Spec Z one day and would hate to go to the trouble of adding a roll bar and then having to remove it to get a cage in.

But a good seat, +Cg lock might be the cheapest, safest way to get a good, secure driver position.

Thanks everyone.

Marty, I think I'm going to sign up for the October THSCC event....and I knew you'd be biased but I know you have experience with other events and wouldn't steer me wrong.

dnguyent

iTrader: (5)

I may have missed something in the postings, but there is also the issue of H&N restraint when using a harness system. I'm more afraid of a head on collision with a wall and the ability of my pencil neck to resist the combined weight of my thick skull and relatively heavy helmet. For that reason, I do not use the harness unless I have a H&N device. The fear of a turnover crosses my mind, but it doesn't cross my mind as often as the fear of neck injury.

I run a 4 pt. roll bar, and it was the compromise I made since I still drive the car on public roads.

91rs13

Back when I drove cars with a Roll Bar or Full cage I was a proponent of not using a Harness bar.
When I made my decision to get a Nismo and keep it as a street car and not a dedicated Track/race car, I tried to stay with the stock 3 pt and seats. This year I added a harness bar, race seat, harness and H&N system. I am so much more in control of the car --I love it. When not on the track, I use my 3 pt.

I weighed the risk in my mind of a rollover and decided that with the better car construction over some of my previous track/race cars ( Datsun 510, 240SX, Am Sedan Camaro) AND the lack of actual rollover accidents I have seen at Track events over the last 20 years ( I organize events and instruct for BMWCCA events in the Northeast) --That it was worth it.

My reasoning was I was more likely to get into an impact with the wall or a Tire barrier ( where the H&N would provide protection) than actually rolling over. Right decision, wrong decision -Who knows. I would prefer a cage, but where I am in life and what I want out of the car --it was right for me.

Not an easy decision to make, but my choice. When I have a passenger/student in my car I do not wear my H&N device unless they have one. I also drive with a little less intensity.