Floor mats and the anti submarine belt

[ThickCobra]

Where do most attach the anti submarine belt? To the floor or the seat frame?

And, if you have floor mats and attach it to the floor how do you avoid drilling a bolt hole in the floor mats? Not a lot of room unless you secure it to the floor under the seat. I'm looking for suggestions.

[wareaglescott]

Mine is through the floor and up under the seat aft of where the floor mat ends.
However I should add I have the Kirkey seats with the pass through for the anti submarine belt so I dont know if a below seat mount is feasible with regular seats.

[Papa]

I'm using the Breeze seat mounts and the anti-sub belt will be attached through the steel plate in the floor under the seat. I'm not sure how the setup would work with the seats flat on the floor.

[edwardb]

I've always used the standard Roadster seats without sliders, e.g. mounted on the floor as far back as they'll go. The attachment for the belt just makes it to the front edge of the seat pan on the frame. Turn the clip around so it's facing back and that gives a little more room. Ends up just behind the floor mats. If you study the Simpson installation diagram, that location isn't 100% ideal. But IMO it works and is way better than leaving it off as unfortunately many do. Keep in mind the main purpose of that belt is to keep the lap belt properly positioned across your hips and not move up into your abdomen in a crash.

[Derald Rice]

Mine is through the floor, under the seat, and it rolls over the front edge of the seat.

In the next month, the car is being re upholstered, and I do not have a belt slot for the sub belt.

so....am having a belt loop stitched to the front of the seat so that the sub belt will be easier to access. Maybe I will remember to use it more often since it will not be hiding under the seat.

[boat737]

I have seat sliders, so the 5th strap is on my seats. I welded a piece of 1/8" bar stock to the front of the seat for attachment. Since my seats are raised about an inch with the sliders, the bar stock helps support the front part of the seat cushion as well.

[FLPBFoot]

Like Papa I'm using the Breeze mounts. Mine is mounted to the floor about 1/2 inch behind the floor mat. Picture is tough in there but you can get an idea. Also I had my my carpet guy cut the mats and install edging so the mat looks better and lays flat.

103614

103615

[phileas_fogg]

I bolted my anti-submarine belt to a piece of 1" square tubing under the front of the seat. In addition to providing an excellent anchor, the tubing raises the front of my seat about 2".


John

https://farm5.staticflickr.com/4513/23606150818_73dde569e4_k.jpg (https://flic.kr/p/BXZGdj)IMG_4126 (https://flic.kr/p/BXZGdj) by jhsitton (https://www.flickr.com/photos/91016165@N07/), on Flickr

[Scott Zackowski]

It would seem to me that if one is using seat (sliding) tracks, it would be best to attach the submarine belt to the seat.

Obviously that way it will move with the seat's changing positions.

[BEAR-AvHistory]

To the floor. Seat is a bad plan because it can tear out on impact. Object of the 5th belt is to keep the lap belt low on your hips when you cinch up the shoulder belts. Its not a submarine belt in our cars.

[ThickCobra]

I have the stock FFR seats and purchased a slider for the driver side to provide just enough adjustment for my 5'8" frame. A lot of work but I'm happy with the result. To make it work, I measured about 2 inches back from the edge of the FFR anniversary floor mats then drilled the 1/2 hole for the clip bolt thru the floor. I then installed both driver and passenger belts while adding some washers to lift the clips slightly off the carpet to allow some strap adjustment. Finally, I installed the seats.

Thanks all.

[swwebb]

Where do most attach the anti submarine belt? To the floor or the seat frame?

And, if you have floor mats and attach it to the floor how do you avoid drilling a bolt hole in the floor mats? Not a lot of room unless you secure it to the floor under the seat. I'm looking for suggestions.

I drilled a bolt hole in the floor mats, which is not all bad. Other people have had issues with the floor mats moving and bunching up, which has caused a number of safety issues. I also pop-riveted my floor mats down so they wouldn't move. The pop rivets worked surprisingly well! They can't be seen, and they held the floor mats down so well that they were a real pain to remove when I wanted to move the mats!! :)

[AC Bill]

It should be solidly anchored to the floor.

I can see the reasoning behind having it attached to the seat frame, for when you adjust the seat forward or back, but for safety sake, you need a much more solid anchoring point. You just have to adjust the length as needed for each person, as you would the lap and shoulder belts.
103720

[JohnK]

Perhaps I'm overthinking this, but I have a concern about the overall effectiveness of the crotch strap. I understand that in this application its primary purpose is to hold the waist straps down vs. it being an anti-submarine strap. However, I'm wondering how effectively it can do this if it's wrapping around the front of the seat and coming back to the buckle vs. coming up through a slot in the seat? In a crash it would be primarily pulling forward on the buckle vs. pulling down on it. I would think that, if using a seat that doesn't have a crotch strap slot, a harness setup that doesn't rely on a crotch strap such as the Schroth Profi II ASM FE would be a better choice, no?

[JohnK]

A little google searching turned this up from the SFI Foundation:

https://www.sfifoundation.com/wp-content/pdfs/guidelines-bulletins/Seatbelt%20Installation%20Guide%2006-05-12.pdf

Top of Page 3 - referring to 5-point crotch belts:

"Crotch Belt should never wrap around the front of the seat – there should be a pass through"

[AC Bill]

A little google searching turned this up from the SFI Foundation:
"Crotch Belt should never wrap around the front of the]seat – there should be a pass through

In the perfect world, sure, this is the best set up, but we only have so much to work with.
Better than not having it at all, which is evidenced by the first time you snug up the shoulder belts without it, and the lap belt becomes a bra..:p

[Scott Zackowski]

It should be solidly anchored to the floor.

I can see the reasoning behind having it attached to the seat frame, for when you adjust the seat forward or back, but for safety sake, you need a much more solid anchoring point. You just have to adjust the length as needed for each person, as you would the lap and shoulder belts.
103720

Good Explanation and makes sense.

I will now plan to attach it to the floor.

Thanks

[1932]

Any good upholstery shop can do the belt hole, it needs to be as in book.

[ThickCobra]

Like Papa I'm using the Breeze mounts. Mine is mounted to the floor about 1/2 inch behind the floor mat. Picture is tough in there but you can get an idea. Also I had my my carpet guy cut the mats and install edging so the mat looks better and lays flat.

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103615

It's winter here in Wisconsin, so I find things to tinker with on my car. One thing I finally got around to addressing was my drivers side floor mat, FFR supplied, bunching up under the foot pedals over time. The floor mats are embossed and very nice, but the spiked backing isn't effective in keeping the mats from sliding forward. I've tried a few remedies but your suggestion to apply pop rivets is rather good and a simple fix.

Thanks

[Paul Mischenko]

Post 89 in my graduation thread has a photo of the carpet which shows where I put the hole. I installed the floor mat, then measured so the triangular bracket could lay flat and the strap would just start to come up over the floor mat. I used larger washer front and back and changed to grade 8 hardware so it all matches underneath. For all the holes in the carpet I heated a socket or a bolt and just burned through. Worked very well, clean holes that won't fray as ends are burnt. I also sat in the car and tried to position the submarine belt right in the middle of my legs where I had my seat positioned so it wouldn't rub if I was wearing shorts. Agree the floor mats slide forward. I haven't yet addressed that. I find I am always pulling them back before I get in.

[GTBradley]

I originally put the bolt a little too far forward, so I had to slot the floor mat, but that ends up keeping the floor mat from moving toward the pedals.
I then decided to buy some anchors and hide them on the backside of square tube and they work perfectly.

https://thefactoryfiveforum.com/attachment.php?attachmentid=119210&d=1576815947

https://thefactoryfiveforum.com/attachment.php?attachmentid=119212&d=1576815973

https://thefactoryfiveforum.com/attachment.php?attachmentid=119216&d=1576816008

https://youtu.be/LgVME-uol4Q (https://youtu.be/LgVME-uol4Q)

I detailed this on page 10 of build thread (near the bottom, if you’re interested).

[GTBradley]

Has anybody had their FFR roadster seat slotted for the 5th belt? It seems easy enough for an upholstery shop to do. I just wonder how it would look and if it is durable.

[ThickCobra]

I originally put the bolt a little too far forward, so I had to slot the floor mat, but that ends up keeping the floor mat from moving toward the pedals.
I then decided to buy some anchors and hide them on the backside of square tube and they work perfectly.

https://thefactoryfiveforum.com/attachment.php?attachmentid=119210&d=1576815947

https://thefactoryfiveforum.com/attachment.php?attachmentid=119212&d=1576815973

https://thefactoryfiveforum.com/attachment.php?attachmentid=119216&d=1576816008

https://youtu.be/LgVME-uol4Q (https://youtu.be/LgVME-uol4Q)

I detailed this on page 10 of build thread (near the bottom, if you’re interested).

I originally tried those anti slip anchors but they did not work. I could not get the steel pins to dig into or under the carpet. I had used lizard skin instead of padding under the carpet. When the carpet is glued to the aluminum flooring, it will not allow the steel pins to set. If I had used something like a fat mat under the carpet, they may have worked.

[GTBradley]

Yeah, I used the ThermoTec and the pins pushed into the mat very solidly. I wonder if they make them with threaded studs? That way you could screw them into a rivnut.