harness with roll cage/bar with back seat

RZG77 · 02-28-2009, 07:18 PM

I have a 78 SC/993 conversion that im restoring, Im looking at installing new seats, and at this point dont have any seat belts in the car, I would like to install 5 point harnesses, this car will be used mainly on the road, and maybe a few track days. What is the proper way to install 5 point harnesses? I do want to be able to use the back seat for my son (sixth months right now) but do so safetly. Is a harness bar safe enough to use? Or a roll bar make the rear seat to unsafe to use? Thanks Ryan

RZG77 · 03-01-2009, 12:01 PM

Nothing????????

Formerly Steve Wilkinson · 03-01-2009, 01:08 PM

This is a subject that has been discussed so much recently that I think people are just tired of writing the same advice over and over. Do a search under both "roll bars" and "roll cages." I assume what you're talking about is a roll bar, since a cage is serious business. For what it's worth, I'm taking out my DAS bolt-in rollbar, which includes high-density padding (the real stuff, not foam), a custom seatback brace and a pair of five-point Simpson harnesses. I've decided it's too dangerous on the street. If you're anywhere near New York, the whole assembly is for sale.

chris.817 · chris.817's Garage

Roll bar, harness bar, whatever, you're not going to get an infant in the back seat. Period.

ChkbookMechanic · ChkbookMechanic's Garage

I just installed a roll cage in my 911 and I agree with chris. There is no way anything is going in the back seat with a harness bar / roll bar / roll cage in the car.

RZG77 · 03-01-2009, 05:36 PM

Thanks for the replies, my main concern was if the back seat was safe or possible to use with a harness bar or roll bar, looks like il be looking for a set of stock seat belts. Thanks, Ryan

175K911 · 03-01-2009, 05:53 PM

Quote:

Originally Posted by chris.817

Roll bar, harness bar, whatever, you're not going to get an infant in the back seat. Period.

I'd be more concerned for the safety of a child in the back with his/her face aligned with the cross bar of the roll bar or harness bar. In a serious impact the child's head would hit the bar causing serious injury or worse.

Get a harness bar and just put it in for those few occasions you go to the track. Use the stock belts for the street. That way you get the best of both worlds.

Formerly Steve Wilkinson · 03-01-2009, 06:42 PM

I've said this over and over again, but roll bars and cages are simply the addition of a huge amount of tubular steel into an interior that doesn't need it. Not only would the poor kid in the back seat do a face-plant into it, but you'll break your spine against it in a hard rear-ender or make like a...well, what was the name of the comedian who sledgehammered watermelons? Gallagher?...in the event of an accident of any sort. Unless it's fully padded and you're wearing a helmet, which is how they're intended to be used.

I fail to understand the rationale for putting these enormous masses of piping inside the close interior of a car that hasn't demonstrated any great propensity for being flattened in accidents. A Jeep Wrangler, maybe. A 911, no.

Well, yes I do understand, since I myself did it under the excuse that I DE'd my car and "would take the rollbar out between events." Which I never did, since it was too much trouble, but the rollbar made me feel like Mister Racerboy on the street. I'm done with that.

chris.817 · chris.817's Garage

That was my point... no one, including an animal, would be safe with any kind of structure in the back. The fact that it's next to impossible to get anything back there with a bar and fixed seats is another factor.

If you can't have harnesses, the CG-Lock is actually a decent alternative.

barney911rs · barney911rs's Garage

RZ,

Getting stock belts is the best idea.

T77911S · 03-02-2009, 05:21 AM

i just bought a KB harness bar for my targa not long ago. very nice bar. i just took it out. we just got a foster baby, so car seat in front and my 13 yr old daughter in the back. there was no way i would put her back there with that bar. just a sudden stop could knock her teeth out.
10 minutes to take out.

T77911S · 03-02-2009, 05:23 AM

i dont quite understand the safety issue steve was talking about though.

RZG77 · 03-02-2009, 09:00 AM

Ill be putting in a set of stock seat belts, i didn't realize that the harness bar would be that of an issue, but wanted to ask since i haven't seen one in a car. I'll focas on getting the car finished then the setup for the track. Thanks to all for the info.....

T77911S · 03-02-2009, 09:09 AM

i dont think the bar is that big a deal. i took mine out so my daughter could get in the back, no big deal. when i need the bar in, i will put it back in.
the bar lets you keep the stock seat belts in too. 4 bolts and the bar is out.

stevemfr · 03-02-2009, 12:00 PM

I meant to post in the other recent thread about rollbars in a street car - never got around to it.

There were some very good points made in that thread as to the pros and cons - I'd just have one point to add: in less litigious countries, the GT3 rollbar is installed ex-factory. And the factory apparently thinks enough of the added safety benefit to put rollbars in cars that prob have less of a propensity to flatten than our older 911's.

Even if one were to argue that Porsche adds the bars as an image item, they don't seem to consider them a serious detriment to safety even w/o foam. Every accident is different and there are bound to be plenty of scenarios where a bar does more damage than good; Steve's wife's rear-ender is a good example. I'd be willing to bet that there are a number of people at the factory who have dwelt on this topic longer and in a more scientific fashion than anyone on this board, tho.

andrew15 · 03-02-2009, 12:01 PM

I think the issues Steve is talking about is the potential for your torso to move 1-2 feet in a collision. Go have a seat in your car and look how close the roll bar is to your head. In an accident it's quite possible for your head to come into contact with it. On a track with a helmet and proper roll bar padding - no big issue. w/o a helmet, well, it's not something I want to think about.

AM

andrew15 · 03-02-2009, 12:03 PM

On the GT-3 picture, note that the seats are an FIA approved carbon/kevlar non-reclining shell and offer way more support and protection than most people have in their DE cars.

stevemfr · 03-02-2009, 02:10 PM

Quote:

Originally Posted by andrew15

I think the issues Steve is talking about is the potential for your torso to move 1-2 feet in a collision. Go have a seat in your car and look how close the roll bar is to your head. In an accident it's quite possible for your head to come into contact with it. On a track with a helmet and proper roll bar padding - no big issue. w/o a helmet, well, it's not something I want to think about.

AM

I understand this - that's why I said that there are bound to be plenty of scenarios where a bar does more damage than good. I still tend to believe that there are people at Porsche who have done more thinking about this than Steve or anyone else here and come to the conclusion that having a rollbar in a street car is not bad.

The GT3 has non-reclining seats but the GT2, for instance, has reclining seats (No, I'm not trying to compare GT2 seats to older 911 seats/whatever). What I'm trying to say is that it's not black and white - in some scenarios your better off w/ a bar and in others not. And the people at Porsche seem to think its OK.

Mr.Puff · 03-02-2009, 03:07 PM

How about harnesses/a harness bar in a Targa with fixed back seats?

Formerly Steve Wilkinson · 03-02-2009, 03:26 PM

I hope we all understand that a "harness bar" is _not_ a place to fasten shoulder harness. It is a guide bar to lead shoulder harness at the proper angle through race seats, the assumption being that the shoulder harness already has secure mounting points (big washers behind the firewall at worst, a rollbar or cage at best).