Topic: harness anchor bolts

rule excerpt:

3.F.2.b Harness Mounting Hardware. Grade 8 or better hardware and 2.5-inch or larger load washers are required when mounting to sheet metal.

I couldn't find anywhere advertising a grade 8 eye bolt of the typical size for a harness snap and my FIA harness came with bolts stamped "8.8" (a metric grade about equal to grade 5).  So I ordered the pyrotect eye bolt with washer kit in the Lemons store (can't post links yet but easy to find)

These are also stamped with "8.8" (they look the same as what came with my harness).  The nut has no grade tick on it, so I will probably throw that away.  The washer is the correct 2.5" diameter.

Is the Lemons store kit legal?  If not, where should I get a grade 8 version of this?

Re: harness anchor bolts

A good source for grade 8 is Tractor Supply if you have one of those close. If you got the kit from the Lemons site I can't believe they would have anything on that site that doesn't meet the tech spec. I typically buy the correct attachment hardware from the harness supplier. I have done it that way about 4 or 5 times.

Re: harness anchor bolts

I usually order them from Teamtech out of Saginaw MI.

4 (edited by gunn 2018-07-11 09:38 AM)

Re: harness anchor bolts

I think I used one of these.

If I had to bet, I bought the bolt that came from Gforce since that is what I used for our first harness.
I suspect that as long as you are using a purpose built harness eyebolt vs an eyebolt that has a split at the bottom where one end of the eyelet meets the shaft (aka something you picked up at Home Depot), you won't get shit for it.
Imagine the force required to shear the nut off the bolt if it's got a washer and the body + plate of your crapcan to pull through


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Re: harness anchor bolts

If my math is correct, a 200lb driver, making a 100MPH impact into a wall, creates 33 Tons of force. Divide that by 5 harness points, and each belt will be responsible for holding 6.6 Tons.

Ask yourself, will this bolt/washer/sheetmetal hold 13,000 pounds?

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Re: harness anchor bolts

75G's is the upper end of what I've seen referenced as a survivable impact. Speed of the crash is just as importance as what you crash into for the resulting crash force.
So 75x(the drivers weight)= crash force (if my math and formula is right, 15,000 lbs. for a 200lb driver.)

Or, how do you feel about standing under that crash force worth of weight hanging from the sides of the harness bolts?

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