How to install new inside tiedown points in the 80?

e9999

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been making do so far in the inside back with the 4 tiedown anchors and the rear seat brackets with cargo ratchet straps. But could use more and better located anchors.
Anybody figured out a good easy way to install more heavy duty ones? How and where?
 
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When we installed 5 point harnesses in our race cars we used thick rectangular steel plates with a hole in the center and a captive nut welded to the back to distribute the force over an area of the sheetmetal.

The ones on my rally car used steel eyebolts made specifically for this purpose. The harness had a clip on the end of each webbing that clipped into the eyebolt connected to the anchor. (The clip was safety wired closed.)

I bought mine from a racing supplier (racer wholesale perhaps?). Any good racing shop should sell them.

You could use this setup to add additional anchor points. I might have one somewhere in the basement if you need a visual. Maybe if I find it I could post a picture? Let me know.

Charlie

PS. Link to something similar -

http://www.racerwholesale.com/catalog/product_info.php?cPath=22_23_28_74&products_id=178

(similar - but ours had a captive nut)

and

http://www.racerwholesale.com/catalog/product_info.php?cPath=22_23_28_74&products_id=184

and

http://www.racerwholesale.com/catalog/product_info.php?cPath=22_23_28_74&products_id=183
 

e9999

You want to do what...?
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CharlieS said:
When we installed 5 point harnesses in our race cars we used thick rectangular steel plates with a hole in the center and a captive nut welded to the back to distribute the force over an area of the sheetmetal.

The ones on my rally car used steel eyebolts made specifically for this purpose. The harness had a clip on the end of each webbing that clipped into the eyebolt connected to the anchor. (The clip was safety wired closed.)

I bought mine from a racing supplier (racer wholesale perhaps?). Any good racing shop should sell them.

You could use this setup to add additional anchor points. I might have one somewhere in the basement if you need a visual. Maybe if I find it I could post a picture? Let me know.

Charlie

PS. Link to something similar -

http://www.racerwholesale.com/catalog/product_info.php?cPath=22_23_28_74&products_id=178

(similar - but ours had a captive nut)

and

http://www.racerwholesale.com/catalog/product_info.php?cPath=22_23_28_74&products_id=184

and

http://www.racerwholesale.com/catalog/product_info.php?cPath=22_23_28_74&products_id=183

not so sure that just sheet metal is enough for heavy toolboxes etc, though...
You think it's fine?


actually, never looked under to see where the OEM anchors attach...
 

IdahoDoug

 
 
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You could check with ScottM on how he had his toolbox secured in a severe collision in January. I know he didn't add any cargo anchors, using whatever was available. The force was so high it crushed the toolbox sides but the box stayed put.

Whatever you use, having a swivel at the attaching point helps maximize the anchor's point by preventing any prying effect.

DougM
 
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e9999,

It is enough that the sanctioning body (SCCA) requires it.

It is safe enough that we trust human lives to it. I've been in a couple of high speed "off"s and the anchor point was the least of my worries. They held up fine.

I think it is probably simialr to how seat belts are anchored in a unibody vehicle from the factory.

I am not an engineer, but someone already put some thought into it.

Not sure what you're going to do that is any more sturdy unless you attach it directly to the frame...

Just sharing my limited experience.

Charlie
 

IdahoDoug

 
 
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Just FYI, you'd never attach a seatbelt to the frame in a body on frame vehicle. Heavy collision with separation of body/frame would slice and dice the passenger. The standard seatbelt attachments to the sheetmetal floor usually use a couple reinforcing sections of high tensile steel (vs mild steel used elsewhere) sheetmetal to spread the load. Belt strap stretch, body soft tissue compression, sheetmetal flex/deformation prevent any energy spikes, so this is way sturdy enough. Same would take place with a 70lb tool box motorcycle strapped to the factory tie downs. I personally have no concerns about them holding an object up to 100lbs in a collision that a human would not survive. The key is having zero slack in the tie down to prevent a force spike. Naturally, use as many tie downs as possible and focusing on a forward moving collision in locating the straps would be logical.

DougM
 

scottm

 
 
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For those occasions where you need the extra tie-downs, you could fasten a couple rails down with the existing tie-downs. Those would distribute the force to the existing tie-downs better than using individual tie-downs. There are various rails made for lifting and mounting, should be easy enough to find and adapt.
 
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scottm said:
For those occasions where you need the extra tie-downs, you could fasten a couple rails down with the existing tie-downs. Those would distribute the force to the existing tie-downs better than using individual tie-downs. There are various rails made for lifting and mounting, should be easy enough to find and adapt.
Something like this?

http://www.macscustomtiedowns.com/scripts/prodList.asp?idCategory=33

I have not used these, but I have purchased other recovery gear from them (and am very happy).

Hants
 
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FYI the Milford system uses a steel backing plate under the sheet metal to help distribute the load (likely for areas where it's not HSS)

Cheers, Hugh
 
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