991 Harness Bar
12-19-2013, 08:45 AM
#17
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Folks,
A few items to add in response to a few thoughts raised:
1. We would never assume anyone would put any child or passenger back there and only ever considered it would be a consenting adult riding to the corner-store during a DE weekend.
2. The reasons for not having an elaborate x-style union were (in order of importance to what we believe were the consumer's wishes): A.) increased rearview spectrum B.) usage of the rear seat areas as storage
3. The entire intention of the x-union is to anchor everything behind the main hoop to a central point, but look at these pieces by themselves. 90% of these "hoops" on the market bolt to the factory seatbelt holes. Ours is no different. adding an elaborate X-design to something bolted with 4 bolts does not reduce chassis flex or increase rigidity, so why block your vision and destroy your cargo room putting one in there?
I think that you guys misunderstood me though or misunderstood what is written on the web site; we aren't saying x-braces make "hoops" less rigid. We are just saying that aren't necessary when they aren't anchoring a main hoop that is welded to the unibody.
My source of frustration is with all of these 4-point bars, hoops, whatever, and the false level of security people have when they think something that does not go forward of the driver will protect in a roll over. I think that all of us agree that if it's going to really really protect us, it needs to A.) provide roll over protection forward of the driver in the event of an A-pillar collapse B.) be anchored to the car with something more than just half a dozen bolts and nuts. In my short 10 years, I have seen some pretty crazy roll overs but on 2 or 3 occasions, when the car has landed on its roof, it has come to rest inverted on some sort of tire wall, k-rail, jersey barrier, whatever, with the a-pillars collapsed.
Maybe no one agrees with me and we are all entitled to our own opinion but if I am installing something that I think will protect me in an end over end rollover, the fact that it's sitting 6" behind me makes me think that my eggs and my groceries in the back are safe, but i'm still exposed.
A few items to add in response to a few thoughts raised:
1. We would never assume anyone would put any child or passenger back there and only ever considered it would be a consenting adult riding to the corner-store during a DE weekend.
2. The reasons for not having an elaborate x-style union were (in order of importance to what we believe were the consumer's wishes): A.) increased rearview spectrum B.) usage of the rear seat areas as storage
3. The entire intention of the x-union is to anchor everything behind the main hoop to a central point, but look at these pieces by themselves. 90% of these "hoops" on the market bolt to the factory seatbelt holes. Ours is no different. adding an elaborate X-design to something bolted with 4 bolts does not reduce chassis flex or increase rigidity, so why block your vision and destroy your cargo room putting one in there?
I think that you guys misunderstood me though or misunderstood what is written on the web site; we aren't saying x-braces make "hoops" less rigid. We are just saying that aren't necessary when they aren't anchoring a main hoop that is welded to the unibody.
My source of frustration is with all of these 4-point bars, hoops, whatever, and the false level of security people have when they think something that does not go forward of the driver will protect in a roll over. I think that all of us agree that if it's going to really really protect us, it needs to A.) provide roll over protection forward of the driver in the event of an A-pillar collapse B.) be anchored to the car with something more than just half a dozen bolts and nuts. In my short 10 years, I have seen some pretty crazy roll overs but on 2 or 3 occasions, when the car has landed on its roof, it has come to rest inverted on some sort of tire wall, k-rail, jersey barrier, whatever, with the a-pillars collapsed.
Maybe no one agrees with me and we are all entitled to our own opinion but if I am installing something that I think will protect me in an end over end rollover, the fact that it's sitting 6" behind me makes me think that my eggs and my groceries in the back are safe, but i'm still exposed.
In the absence of that analysis, alternate means to evaluate the system are (a) judgment and (b) review of test/crash data, the latter being far preferable. My own data set, even adding what I've heard from others, is pretty small. With Porsches, here are the outcomes I've seen or heard of with rolls:
- No roll bar/cage, and the roof doesn't cave.
- Roll bar present, but not used because the roof doesn't cave.
- Roll bar present and prevents caving of the roof locally, A-pillar(s) cave, but roll bar still protects the driver by keeping the roof high enough over the driver's head.
- Roll cage present and driver is protected.
Again, my data is limited, but I've not seen or heard of these cases:
- Driver injured due to A-pillar caving despite roll bar doing its job locally.
- Roll bar itself failing.
- Bolted roll cage failing.
If others can report what they've seen and heard, maybe we can collectively get a better sense of what really works and doesn't.
12-19-2013, 09:26 AM
#18
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All of that data seems pretty sharp to me. I think that unfortunately, the only way to do real research would be to look at every single roll-over case individually and look at what failed and what didn't. I can only speak to our harness bar and tell you that our single biggest focus was on the rigidity of the cross bar and it's ability to do what it is there for and that is to not bend or break where the shoulder -harnesses are anchored and the car has a head-on impact.
We can probably bench-race this until the cows come home but maybe I'm just very old school in my thinking; to me, 4-point "harness bars" are show bars and we don't represent them as adequate rollover protection and usually suggest a 6-point or a weld-in if we don't want anything left to chance. Maybe in the history of DE and racing, an A-pillar has never collapsed to the part of injuring the driver. That doesn't mean that it provides the same level of roll-over protection, does it? Just because people aren't getting crushed by a-pillars at DE events doesn't mean it can't happen.
Trying to find a right answer to this question is probably like asking someone if they think they should solder or butt-connect. We all have our opinions. I'm just way too hesitant to advertise these things as roll-bar when they aren't roll anything. I have seen "4-point roll-bars" bolted to the new 981/991 aluminum floors in multiple points and I don't think that's adequate either.
We can probably bench-race this until the cows come home but maybe I'm just very old school in my thinking; to me, 4-point "harness bars" are show bars and we don't represent them as adequate rollover protection and usually suggest a 6-point or a weld-in if we don't want anything left to chance. Maybe in the history of DE and racing, an A-pillar has never collapsed to the part of injuring the driver. That doesn't mean that it provides the same level of roll-over protection, does it? Just because people aren't getting crushed by a-pillars at DE events doesn't mean it can't happen.
Trying to find a right answer to this question is probably like asking someone if they think they should solder or butt-connect. We all have our opinions. I'm just way too hesitant to advertise these things as roll-bar when they aren't roll anything. I have seen "4-point roll-bars" bolted to the new 981/991 aluminum floors in multiple points and I don't think that's adequate either.
03-19-2015, 07:30 PM
#19
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Orbit Racing sent pics of this most recent customer install for a 991 GT3. And to clarify, it was never intended to put a person in the back...just your oversized Ogio or Sparco gear bag that won't fit under the bonnet!
03-19-2015, 09:05 PM
#20
To what points of the car does the bar bolt?
04-06-2015, 12:45 AM
#21
Found the answers to my own question. This harness bar bolts to the seatbelt anchors in the front, and the strut towers in the back.
04-06-2015, 10:31 AM
#22
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P.S. Yes...it's time to retire the Passport 8500 power cord!
04-06-2015, 10:58 AM
#24
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Yes Peter. Realizing that you're 6'4 or so, if you want I could call the folks at Orbit to confirm that we retained almost 100% of the seat track availability to accommodate even the tallest of driver.
04-06-2015, 11:01 AM
#25
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Long legs, pleasantly surprised howmuch room there is in the new GT3 so I want to use that all..
I'll ask when I'm there, Rodger still working on my 964, will pick it up soon.
04-06-2015, 03:06 PM
#26
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Since all I really want is a harness bar, this looks great to me. Love the full view out the rear. Any chance you could post a working link to the webpage? The link in the first post doesn't work for me. Thanks.
04-10-2015, 06:36 PM
#28
04-11-2015, 07:48 AM
#29
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We are undergoing a web site revision and will hopefully have a shopping cart function soon.
Thank you!
04-11-2015, 07:49 AM
#30
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