MGB Grade 9 bolts

[Rut]

Has anyone ever used grade 9 bolts from Fastenal? I understand that they are just a little stronger than grade 8 and can be used when the are spec.
Thanks, Rut
https://www.fastenal.com/content/feds/pdf/2017/02/High Strength Bolts rev 2017-02-21.pdf https://www.fastenal.com/content/feds/pdf/2017/02/High Strength Bolts rev 2017-02-21.pdf

 

[PAUL161]

If a grade 8 bolt won't hold it, then there are other problems that need attention first. Never used a grade 9 bolt on anything, as a matter of fact, I never heard of one and I buy bolts at times from Fastenal. Not saying there aren't bolts or studs stronger than a grade 8, as there are, but I've found their rated by torque, stretch or shear strength not numbers. New one for me. PJ

 

[DrEntropy]

Me too, Paul. Seems like more a sales gimmick than any practical application. If a spec. ASTM grade 8 bolt is used, what could be better? "Oooh!! There's a GRADE 9 available!"


BAH, HUMBUG. :smirk:

 

[Rut]

Thanks for the replies and the reason for this post is twofold: 1, the specs on grade 9 and ARP fasteners are similar and the reduced amount of stretch at the same torque is appealing to me. The downsides when used in applications where grade 5 and 8 were used are few as far as these cars are concerned, imho. 2, Fastenal has them on sale in fine thread and I’ve been buying 1/4 thru 3/8 in a variety of lengths for $4-$6 a box. In a critical application I use what’s susposed to be used, but where grade 2 imported stuff is your only choice at the big box stores I like the grade 9...stronger and cheaper.
Thanks, Rut

 

[DrEntropy]

but where grade 2 imported stuff is your only choice at the big box stores I like the grade 9...stronger and cheaper.

Certainly. The taffy fasteners from big boxes may be okay for putting up the screen doors, they aren't much good when it comes to automotive suspension or engine applications. "Stronger and cheaper" decidedly wins.