3 Point Seat Belt Install

[2067Bug]

Hi,

I’m about to install 3 point retractable seat belts in my 57 bug. The car is stripped to include all the interior and is waiting to be painted. I know there are no factory mounting holes on the 57.

I also have a 67 bug where I used the pre-drilled B pillar holes to mount the retractable mechanism and the pre-drilled holes in the tunnel to mount the stiff arm. Please see pictures below.

My question is - should I use the same location on the B pillar of the 57 for mounting the retractable mechanism, and drop down directly below the pre-drilled hole in the tunnel to the floor pan to mount the stiff arm? I do not want to disturb the tunnel. I realize that by going to the floor pan with the stiff arm it will add about 5” to the length of the stiff arm. Does my plan seem reasonable?

Thank you for your help...

[Snort]

If the height of your 67 B pillar mount works for you then you should use that same height. I've had some issues with earlier Bug and Type 3 that had factory B pillar mounts and they were too low for my comfort.

I think you should reconsider using the tunnel for your 'stiff arms'. The tunnel has very thick metal and as such is easy to weld and provides more than enough structural support. Once done, no modification necessary to the 'stiff arms'.

[2067Bug]

Snort - thanks for the reply.

I agree that the tunnel is the ideal place to anchor the stiff arm, but the risk of drilling into it may outweigh the gain. After reading a lot of posts, I cannot pinpoint the exact location that guaranties not to hit or disrupt one of the tubes. As for the retractable mechanism, I was assuming that the pre-drilled holes on the 67 were the best place based on engineering design and hopefully safety approval.

Thanks

[2067Bug]

Does anyone know if I would hit one of tubes or spot welds in the tunnel if I drilled in the same location as the pre-drilled holes in the picture? If so, do you know where to drill the hole without hitting anything?

Thanks

[hopkin]

I saved these cutaway photos from another thread a while back, I hope these help you visualize what's inside the tunnel. I'm not sure of the year of the car these are from...

_________________
1971 Super Beetle (past)
1971 Super Beetle (past)
1974 SunBug (past)
1972 914 (past)
1991 Honda Civic (Original Owner)
1996 'Open Air' Mexican Beetle (current)
2015 Golf (current)
2017 Dune Edition (daughter's car)

[2067Bug]

Hopin,

Thank you for the pics. Yes, I have seen them before and they are excellent. On the 57 there is also he choke cable tube. I’m surprised that with all the posts I have read about seat belts and safety concerns with ovals, I cannot find a picture showing the exact location in the tunnel for the stiff arm bolt. I have all the Bug Me Videos, and they do not cover it either.

I thought I had the answer when I reviewed Juliano’s Seat Belt installation instructions for a 1950 beetle. Unfortunately, the last step shows the stiff arm being installed into the tunnel of a much later year bug with a pre-drilled factory hole. I’ll keep searching for the answer and post more when I find it.

Thanks

[Rome]

2067, here are some ideas. For the tunnel mounts, how about welding a sturdy nut (M10 thread or the appropriate SAE size?) onto a larger plate such as a 1600 engine oil pump cover, then weld the entire plate onto the side face of the tunnel? This saves you from drilling into the tunnel.

As to the B-pillar, 25 yrs ago I had a late '52 Beetle on which I also wanted to install 3-point belts. I had a '74 Beetle parts car on which I cut the B-pillar about 6" above and below the upper belt mount. I saw that the belt mount had a reinforcement piece welded to the inside of the pillar, which consisted of a slightly curved with the M10 nut welded to the inside, facing into the empty pillar chamber. I chiseled the reinforcement off the pillar sheetmetal, which ended up being about 8" long. Then I positioned the reinforcement on the outside surface (facing the interior) of the '52's B-pillar, and drilled a hole in the pillar just below the bottom of the semaphore box. The hole was large enough so that the weld nut on the reinforcement fit into it. This way I was able to surface-weld the entire reinforcement flush on the surface of the pillar. The height corresponded approximately to that of the '62 thru '65 locations. Once I had placed padding over it and pulled the pillar vinyl back over, the slight thickness of the reinforcement which was about 1/8" was not immediately noticeable. You could do the same method for yours, but placing it at the same height as your '67.

Another idea- I vaguely remember the official VW repair manual for the late '50's has a procedure to install lap belt holes into the tunnel. The big Bentley manual thru '65 most likely has this procedure. Maybe it's even partially shown in theSamba. The factory procedure would certainly provide measurements to avoid cutting into any pipes on the inside of the tunnel.

My '52's lap belt was easy to install, because the body was on the '74 parts car chassis which of course had the factory mounts in the tunnel.

[2067Bug]

Rome,

Thanks for the options. I did consider having a plate welded to the side of the tunnel as you suggested. It seems like a practical solution and one that would be used for situations like mine. I’ll ask the welder putting the belts what he thinks in terms of safety.

With all the seat belt kits being sold for VW bugs, you would think that someone would make a plate with a welded nut as part of the hardware installation. I’m not sure which is safer, welding a plate to the tunnel or to the top and bottom of the floor pan.

Thanks

[2067Bug]

Rome,

How about some like this welded to the tunnel? These are from Juliano's Seat belt hardware kit, which I considering buying.

Thanks

[Rome]

Like these, though if they were mine I'd have the nuts welded all around onto the base plate, not just with the two weld blobs. https://www.ebay.com/itm/Racing-Harness-Seat-Belt-...0677.m4598

I just saw you posted while I was still writing mine... IMO the top bar could be considered for a tunnel mount, since it is very sturdy. It would need to be welded all along the length top and bottom, and then you'd have the thickness of the bar to hide with padding. The bottom one IMO does not have nearly enough surface area for welding the perimeter to the tunnel. The idea is good, to have the nut facing the tunnel and the plate formed so that you end up with flush mount edges. But for an aftermarket or self-built mounting plate I would go no smaller than the original factory mount reinforcements. Something like at least the size of a business card. Here's the factory-original floor lap belt mount on a '65 for size reference-

Some other ideas come up using this search- https://www.thesamba.com/vw/forum/album_search.php...t_dir=DESC

[2067Bug]

Thanks - I like the STR setup and plan on calling them to find out more. The bar does look very sturdy and the rubber mats I am using should hide it well. I'll also check out the seat frame distance to ensure enough clearance. When I get this all sorted out, I post the results.