Roll Bars vs. Harness Bars

[JRitt]

We are preparing to release our harness bar for the FT86, and I wanted to start a thread to discuss using one vs. the other. I'd like to keep the other thread uncluttered and exclusively focused on product details. A forum member wrote the text below. Feel free to discuss. You can make up your own mind if a harness bar or roll bar is right for your needs. Thanks.

In the case of a cage or roll bar, the harness is attached to a construct that is in itself very rigid, so that in the event of a crash the belts function properly while their mounting locations remain static. My own personal and at this point theoretical concern is that your bar mounts to a location that, while rigid and supposed to protect both side impacts and rollovers, is still designed with crumple in mind, therefore I can only imagine what would happen in a direct impact to the pillar zone forcing the bar to shift. If it shifts forward the belts loosen, if it shifts backwards the belts will tighten, both are dangerous scenarios.

Please disprove my concerns.

[rice_classic]

I sit on the same side of the aisle as the person who posted that. I won't wear a 5pt or 6pt belt without a roll hoop. I want my body to be able to move when the roof collapses during a rollover and the FRS doesn't exactly have a sturdy roof. If I need a 4,5, or 6pt harness then I need a 4pt rollbar. That's just me but I don't believe in a after life so I take safety pretty seriously.

Back in 2010 an incident in a civic using Sparco belts and harness bar like what is offered went viral throughout all the automotive enthusiast boards. A front end impact and failure of the harness bar resulted in the driver being ejected out of the car. I don't remember if he survived or not.


To quote an excellent post regarding that event of the driver being ejected (since all photos of the incident have been taken down), he makes good point while also describing the failure:

Sure! First, see how the bar is bent right in the middle? That was apparently caused by the belts pulling the bar forward (from the passengers being thrown forward when they hit whatever they did). That alone is just TERRIBLE. Either through design, construction, or material choice, something got really f*cked up there. I've seen plenty of accidents on track and otherwise with a rollbar/cage where that did not happen, and the occupants remained properly secured. Hell, I've been in one, a front-end collision into a tirewall, and everything worked right.

While the design of the bar does leave a lot to be desired, I'm thinking its just too small of a diameter with too thin of a wall thickness. Both of those = weak bar.

Second, the passenger was thrown through the windshield. This probably happened because when the bar bent the shoulder straps went slack and no longer held him/her in place, allowing them to come free. A lap-belt alone will NOT save you here. If you're curious about just what happens to the body in an accident, there are some great crash testing videos on youtube. It is an eye-opener.

Ultimately, people will continue using this, and thats their decision. For autocrossing its probably still fine, as the point is to hold you in place better than the stock 3-point belt and it does that (which is what a lot of people say: "it works well for holding me in" Have they crash-tested it?). However, the big assumption there is that you won't hit anything. Chances are slim, but not impossible. On the street, well... You can say, "Oh, I won't hit anything, I'm a safe driver" but then look at this guy. What I really wanted to do here is just make people aware of the potential consequences of a product choice, not instill fear.

It's then followed up with this. Which is important because it addresses the importance of quality vs knock-offs. However I still stand by other concerns that are non-knock-off related.

The research is pointing towards the bar being an ebay knockoff, rather than a genuine Sparco unit. We all know the kind of compromises that often go into such a product, and that could largely, if not completely, be the cause of such a catastrophic failure. However, from this one could also infer the dangers of using a generic (or possibly big-name) rear strut bar as a point of attachment for shoulder straps. Those bars are DEFINITELY not designed for resisting such a lateral load.

Ultimately, my point with any safety-related issue is this: know what you're dealing with, educate yourself on potential issues or consequences, and accept responsibility for your choices.

So while I like to lean on data to make decisions in this case it isn't available and I'm going to "err" on the side of safety. However I would love to see data but I don't see a firm putting up large sums of dollars to do a bunch of crash testing of these in actual cars to prove anything, especially when there's no regulation regarding these and they sell easily to be folks that don't give it much thought or simply don't care.

[rice_classic]

On principle I feel that when anyone is selling anything that is claiming to make one "safer" the burden of proof should be on the supplier. Otherwise the proletariat can find themselves surrounded by a barrage snake oil salesmen claiming to "make them safer" when indeed the opposite is true and my safety and the safety of others should be treated with dignity and respect.

Consequently, if this bar is advertised for "autocross use only" or has a big disclaimer that it is "not a safety device" then that's a little more ethical even though plenty of people would disregard such wording and use in place of very safe and very proven OEM 3pt harnesses for all applications. But C'est la vie. If and only if claims of increased safety are made then I feel the seller should be required to PROVE IT. For anyone to claim that "there's no proof that a thing is less safe" is an argument for it being safe is ridiculous and such an argument should be immediately disregarded and discredited.

I also deliberately did not post in your other thread. I know you're just selling a product and I can respect that but as always; Caveat Emptor.

[Dave-ROR]

I see people use these all the time for autocross. I'm fine with it as long as people understand what it does, and doesn't do.

I would never allow a car with a harness bar on track. Period, end of discussion.

Same goes for having 1 or 2 of the following items, but not all three: Roll bar/cage, fixed back seats, harnesses.

If you have any one only, nope. Any two only, nope. All three, yep.

[housecat]

Thanks for the posts everyone. I'm learning a lot about roll bars and related stuff. Before I did some searching, I thought a roll cage by itself would make me safer! I have a lot to learn

[Totality]

The Essex "harness Bar" is a piece of engineering artwork. All vendors could learn from the Essex's build quality, fit, finish, and documentation. People spend hundreds of dollars on strut braces. This bar tightens up the whole car. I had to loosen up my coilovers after installing it. The thought that went into this bar's design and the precision of manufacturing still amaze me.

From engineering stand point I have no fear of this bar ever failing. I like using a four point harness on the track. It holds me in place so I am more relaxed making me a better driver.

Safety discussion get very hot very quickly on boards so I am not going to go there.

This car is my DD. I only use the harness on the track.

I love this bar and appreciate it every time I drive.