Qa1 Frame Hardware

[71Scamper]

So I got my new Qa1 K-frame (t-bar, stock steering) and was setting up to begin the install and noticed the frame to body bolts that came with the kit were grade 5. So I looked at the factory bolts and sure enough they are grade 5. I would have thought that being a critical bolt and only 4 of them holding the front end on, they would be of grade 8? Any idea what the thought was behind this? Maybe so they have a little give on a hard impact instead of snapping?

 

[Jeremiah (jd)]

I have uses the QA1 supplied bolts on several cars with no issues. A tech once told me that they sourced their h/w from Fastenal.

I would make some sleeves to better locate the forward mount to the bolts. I am 95% that I used 5/8" .083 CM for the locators.

 

[72bluNblu]

So I got my new Qa1 K-frame (t-bar, stock steering) and was setting up to begin the install and noticed the frame to body bolts that came with the kit were grade 5. So I looked at the factory bolts and sure enough they are grade 5. I would have thought that being a critical bolt and only 4 of them holding the front end on, they would be of grade 8? Any idea what the thought was behind this? Maybe so they have a little give on a hard impact instead of snapping?

Because the grade 5 bolt strength far exceeds what it needs to be in order to hold together the stamped sheet metal of the K frame and frame rails.

There is the possibility that the grade 8 bolts are slightly less ductile, but realistically the tensile and shear strength is much higher so the while the high carbon steel might be slightly more brittle it really shouldn’t fail at any load that’s below than the grade 5. Maybe on a long term analysis it might be more likely to develop cracks, but I’d say even that’s fairly unlikely.

Realistically even the grade 5 bolts are more than enough, the frame rails and K frame would fail first.

 

[Cuda416]

That joint is not as rock solid as some might want to think. Grade 8 are indeed stronger but Grade 5 will take more of a beating because the will "move" where a grade 8 won't will resist that, and will crack before g5 in that regard. Now if you're bolting a 1 inch plate to another some other massive par that will NOT move, grade 8 is where you want to be. "Stronger doesn't mean better".

 

[ProjectBazza]

A tech once told me that they sourced their h/w from Fastenal.

Correct. An ex-neighbor (we moved 3 years ago) works for Fastenal, and he told me the same thing. I think a part of this is because it's cheaper to keep everything within the same State (reduced shipping costs, simpler Manufacturing communication, etc), but I've slept a few times since then so I don't recall everything.

 

[71Scamper]

I have uses the QA1 supplied bolts on several cars with no issues. A tech once told me that they sourced their h/w from Fastenal.

I would make some sleeves to better locate the forward mount to the bolts. I am 95% that I used 5/8" .083 CM for the locators.

View attachment 1716396451

I'm having a hell of a time trying to find online the size tubing you used as spacers. do you have a link to site that I can grab some of this chromoly tubing from? Thanks!

 

[Jeremiah (jd)]

I will measure some in the shop and reoort back