Feasibility of adding middle row seat belt anchor?

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If one of this guy's kids dies, do you intend to be at the funeral?
Probably not. Not that it has anything to do with this information.

This is an internet forum, not a paid expert advice.

All the fear of litigious action is part of what has destroyed our society because people don't take responsibility for their own actions.

Take a peek at what GM and Toyota are already doing for anchoring to the floor behind the seats anyway.

Can't get blood out of my turnip.
 
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Been thinking about seating 5 (I have 3 boys) and still kitting out the 3rd row area of my 80 for drawers/sleeping. I have the third row seats, but it would be a pain R&R-ing those all the time.

How feasible would it be to add a shoulder belt anchor for the middle seat? My first guess would be bolting it to the roof somehow, and a clip on the top of the seat back for routing/comfort.

Am I crazy? (I know that answer...)
Early 80's, through '94 I believe, had 3 belts in the second row. The middle is just a lap belt, but it was considered good enough at the time, and if you're concerned about modern safety standards you should buy a modern car. I'd find an early set of second row seats before trying to rig something to the roof- which will likely not be anchored properly without adding an additional structural crossmember.
 
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Early 80's, through '94 I believe, had 3 belts in the second row. The middle is just a lap belt, but it was considered good enough at the time, and if you're concerned about modern safety standards you should buy a modern car. I'd find an early set of second row seats before trying to rig something to the roof- which will likely not be anchored properly without adding an additional structural crossmember.
I have a lap belt in the middle. Want a shoulder belt there.

I can anchor to the existing points, just would need a longer belt side and an attachment point for the loop on the roof.
 
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I have a lap belt in the middle. Want a shoulder belt there.

I can anchor to the existing points, just would need a longer belt side and an attachment point for the loop on the roof.
Ah. Maybe it was the third row with the extra lap belt in earlier models, I don't remember.

In any case, seatbelt systems are engineered to a ridiculous degree, because they have to be. Personally, I wouldn't make any alterations to them. So I vote 'crazy'.
 
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Just use the lap belt. Sheesh.
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jellis

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In any case, seatbelt systems are engineered to a ridiculous degree, because they have to be.
I thought that was the case as well but it turns out that's not really true. Thumbing through the above standard (specifically the element I quoted around reinforcement of anchoring attachment points) makes it clear that these are very simple systems from an engineering perspective. I mean, it literally says "You need a 7/16-20 or 1/2-13 bolt and an area of sheet metal with reinforcement added at least 1.5mm thick covering an area of 4 in2 minimum." Do that at three points and connect them with webbing of a specified strength, you're done. It really doesn't get more simple than that.
Rollover performance, air bags, and crumple zones/other design elements intended to reduce impact force transmitted through the seat belt system, that's where the engineering budget goes. And metallurgy, I've done extrication training for my volunteer fire department and it's amazing how strong the metal is in cars now--your typical A36 steel plate has a tensile strength of 36k psi whereas the metal in most car frames today is 145k psi, so literally 4X stronger than most of the stuff you'd use at home!

To avoid puncturing the roof with a bolt, you'd need to setup an attachment point equivalent in strength to the above-stated specification via welding a reinforced captive nut. Ideally in a cross member, but apparently that's not a strict requirement.
 

iptman

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Maybe just leave one of the two 3rd row seats in and build a custom drawer system just for the one side? No one is going to want to sit in that middle seat for too long. I have a similar dilemma (but with 4 kids) and ended up buying an M416.
 
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How old is the youngest? Young enough to sit in a fwd facing child restraint seat (do you even have these in the US?)?

The regulations are significantly different in Australia around seatbelts but in the past I've used a childs seat designed for use with the OEM lap belt, plus had the upper tether go back to either a floor mount, or a mount in the rearmost structure of the roof. This means the seat is tethered to the car, and the seat has it's own over-shoulder harness for the young-un.

There simply isn't enough structure across the centre of an 80 series roof to hold an upper mount for a lap/sash belt.

Also, NEVER have a shoulder belt upper mount point below shoulder height. As the human travels forward into the belt in a crash it pulls down on the shoulder causing spinal injury.
 

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