Bolt Spec for Engine Stand? (1 Viewer)

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jaymar

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Was given two perfectly-sized bolts for this, 90mm long, "8.8" and what looks like a tie fighter stamped on the head. Need two more. Anyone have the thread spec handy? And do you figure 8.8 will do the trick? Maybe 16mm of thread goes into the block before it bottoms out. Thanks for any help!
 
12mm x 1.25 x 30mm is the standard trans bolt so you add 30mm + whatever length your engine stand arms are. EDIT pitch is 1.25! My apologies.
 
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12mm x 1.75 x 30mm is the standard trans bolt so you add 30mm + whatever length your engine stand arms are.
Thanks! 90mm perfect for these stand arms.
 
Looking at McMaster-Carr site, no metric bolt I'm seeing has a grade rating, and the specs say hardness not rated. If I want to get an 8.8, it has to be SAE. This despite the fact that I have two metric 8.8 bolts in my hand, which I'm told came from McMaster-Carr. Site lists tensile strength on the metrics as 100,000 psi, which is quite a bit below Grade 8. These bolts are 18-8 steel. Does this make any difference, or am I splitting hairs here? Engine has all accessories in-place. Thanks for any help!

 
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I got mine local at a hardware store and they had 8.8 or 10.9 grade. Home Depot has them also
 
You got a rebuild your doing?
 
You're splitting hairs.
Your Chinese engine stand will fold in half before you snap a 12mm bolt holding a static tensile load.
The bolts only need to be tight enough to hold the engine in place. You shouldn't need to be torquing them enough to stretch the bolt.

Strictly speaking the definition of grade 8.8 is not applicable to a metric fastener.
10.9 is roughly equivelant to 8.8

if you want to figure it out . . .
 
Looking at McMaster-Carr site, no metric bolt I'm seeing has a grade rating, and the specs say hardness not rated. If I want to get an 8.8, it has to be SAE. This despite the fact that I have two metric 8.8 bolts in my hand, which I'm told came from McMaster-Carr. Site lists tensile strength on the metrics as 100,000 psi, which is quite a bit below Grade 8. These bolts are 18-8 steel. Does this make any difference, or am I splitting hairs here? Engine has all accessories in-place. Thanks for any help!

Not sure what you are looking at but McMaster does have graded metric fasteners. You can get 10.9, M12x1.75x90mm

I think people are confusing SAE and Metric ratings. Metric are 8.8, 10.9, 12.9, etc, SAE is 2, 5, 8, 9. An 8.8 is roughly equivalent to an SAE grade 5.


"ISO Class 10.9 fasteners are metric high-strength steel screws and threaded rods. They're commonly found in valves, pumps, motors, and other high-stress applications. They have a minimum tensile strength of 150,000 psi. Use them with Class 10 or higher nuts."


 
"Your Chinese engine stand will fold in half before you snap a 12mm bolt holding a static tensile load."

:rofl:
 
Not sure what you are looking at but McMaster does have graded metric fasteners. You can get 10.9, M12x1.75x90mm

I think people are confusing SAE and Metric ratings. Metric are 8.8, 10.9, 12.9, etc, SAE is 2, 5, 8, 9. An 8.8 is roughly equivalent to an SAE grade 5.


"ISO Class 10.9 fasteners are metric high-strength steel screws and threaded rods. They're commonly found in valves, pumps, motors, and other high-stress applications. They have a minimum tensile strength of 150,000 psi. Use them with Class 10 or higher nuts."


:eek: I did NOT find those suckers, though I was looking for SS partially threaded. Hmmm...
 
You know it's true, right?? :hillbilly:
That's why it's funny. Though it does seem like an awful lot of weight to hang by a few bolt-tips, any way you cut it.
 
Anyone care to guess again on that bolt spec?

Assuming McMaster-Carr sent what I ordered, that’s the wrong (or incomplete) spec. Bolt that fits is on the right.

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Head bolts? Not at those prices, though I’m now $25 into the wrong bolts… 😕
 
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Not at those prices, though I’m now $25 into the wrong bolts… 😕

Can you return them?

Did you end up confirming thread specs with ARP?

I think I discovered steering box to frame bolts are the same thread, and similar length.
 
Can you return them?

Did you end up confirming thread specs with ARP?

I think I discovered steering box to frame bolts are the same thread, and similar length.
Does anyone know, FOR CERTAIN, what this spec is?


MG: No idea on returns. Have ARP custom studs ready to test-fit at machine shop. (If I can ever get this engine on the stand...)
 
I'm told these are the ticket:

 
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