What Hardware Is Required To Mount Shoulder Harness in 356C?

[Greg Carter]

I was planning to install some 3-point non-retractable seat belts in my late 356C coupe and wasn't sure what I actually needed to install the shoulder harness per the factory (lap belt hardware is already there). I beleive I only need these (plus the seat belts):

https://www.stoddard.com/90180312700-nla.html.html

https://www.stoddard.com/90180312321-set.html.html

Is there anything else?

Greg

[Mike Wilson]

I think it will depend upon the seat belt end. I have the PEP retractable seat belts so my attachment is different. I'll try Googling the topic to see if there are any pics.

Mike

[Mike Wilson]

Sorry, no definitive pics or info. Hopefully someone who has installed them can advise you.

Mike

[Martin Benade]

On mine i drilled and rethreaded the factory 8mm shoulder belt anchors. They are mounted a bit lower than ideal but not that bad, especially since I’m not that tall. I think the mount is very beefy. I have been told an 8mm bolt is strong enough but no modern car ever uses that small size.

[Martin Benade]

On mine i drilled and rethreaded the factory 8mm shoulder belt anchors. They are mounted a bit lower than ideal but not that bad, especially since I’m not that tall. I think the mount is very beefy. I have been told an 8mm bolt is strong enough but no modern car ever uses that small size. The Stoddard bolts etc are the 8 mm ones that I’d upsize.

[Mike Wilson]

Wouldn't the bolts offered by Stoddard and probably others have to meet DOT standards?

Mike

[Greg Carter]

The belts are non-retractable.

The belts I’m looking at appear to use a “stock” 356C mounting arrangement based on the pictures. I believe the original / factory style shoulder harness mounting hardware is what I need.

I’m just not exactly sure what all is included in this mounting hardware so I was trying to figure it out

Greg

[Mike Wilson]

Pretty sure you only need the second part listed, the one for the shoulder strap.

Mike

[Martin Benade]

The factory belts just hooked onto the aluminum knob, and the Stoddard kit is just an old car replacement part, definitely not DOT-approved. DOT didn't exist until 1967.

[Mike Wilson]

Good question to pose to Stoddard as they are selling them for shoulder belts. I agree having a larger bolt would be a safer alternative.

Mike

[Norm Miller]

I think the body sheet metal would rip before the bolt broke and your body would be somewhat damaged before the bolt would break.
My preference is the retractor type.
My C has a nice setup.
I have no idea where you're located so can't give a reference.

Norm

[Dave Wildrick]

Greg,
The hole in the center of the attachment flange welded to the car has a larger diameter than an 8mm bolt. In your picture of the Stoddard kit, the silver (aluminum) piece that the shoulder belt clips onto has a base that acts as a spacer between the bolt diameter and the hole’s diameter. This is probably to spread the force when the shoulder belt pulls on it. In my 65C coupe, I used the PEP retractor belts, with the retractor fastened using a similar 8mm bolt; however, I inserted a stack of steel washers on the bolt shaft for reinforcement to spread the force in a similar fashion to what the Stoddards’ aluminum spacer does. You might contact Bill Sargent (of this talk list), who is now in Washington state I believe, as he spent considerable time attaching the shoulder belts in his 65C cabriolet, and he is an engineer and a stickler for correctness.

[Ben Wainscott]

When I completed restoration of our SC in 2007, I installed a set of 3 point non-retractable seat belts at the stock attachment points (I believe I bought thru Emory's). Included in the kit were two cylinder head barrel nuts that just fit in the back attachment point and the 8 mm bolt went thru them.

[Al Zim]

DO NOT UNDER ANY CIRCUMSTANCES USE THE SHOULDER MOUNTS IN THE 356C CARS TO MOUNT YOUR SHOULDER RESTRAINING DEVICE. Follow the instructions outlined in the last section of the shop manual. If you remove the upholstery around the 8MM bolt you will see that the support is 4 thin pieces of sheet metal that look like a stool and hold the bolt away from the body of the car. If your shoulder harness breaks loose you will impale yourself on the steering column which is a solid rod connected to the steering box that will not move. The steering coupler will not break! This will hurt you and if you have a wooden steering wheel plan on a lot of facial surgery. al zim 2019/04/11 I am sure this will get some response.

[Mike Wilson]

It would be interesting to know the amount of force that would shear the factory mount as compared to the DOT standard. I wonder if the factory mount could be reinforced to that standard.

Thanks for your description of the mounting point, Al.

Mike