Knuckle Stud conversion questions....

Hello gang!

OK, I've checked out the tech section, but still am a bit unsure of a few things....

Firstly, all roads point to using studs EXCEPT this past issue of Jp magazine, where Willy Worthy mentions using grade 8 button head bolts threaded through the inside. Is there any advantage to using studs as opposed to the bolts brazed into place on the knuckle?

Secondly, it's not real clear as to how much material to remove for the 9 and 3 oclock stud heads. Vernco uses a counterbore to clean up the knuckle casting for the studs. If I took off just enough material from the knuckle to be sure that the stud or bolt head is as proud as the original casting was, is that too much? Also, am I correct in thinking that the deepest counterbore would only be at 3 and 9 oclock, and the others wouldn't need nearly as much?

Any advice on the subject is appreciated. TIA!

 

The sets that I have done for the guys on this board I did not do the 3-9 o'clock positions just the others, used bolts in the 3-9 position unless there already stripped out (I have done probably about 6 sets). As far as the counterbore goes you don't want to remove more than about a 1/32" worth of material, just enough to give a flat even spot, about 50-75% of the inside of the stud head. I always do mine to the same depth on all 4 places. Studs are also better than using button heads, running a thread up to a shoulder like the button head would is gonna weaken the casting unless you chamfer the inside of the hole for the crappy last thread on the screw. All American made cap screws, button head, socket head and lowhead and such are grade 8. If you do the studs in the 3-9 position you remove the material from the backof the stud after its pressed in, and you counterbore these to the same depth as the others. Also chamfer all the holes inside before pressing the studs in. My.02¢

 

Hmmmm, Vernco sez this....any thoughts?

 

In the drawer at the back of the shop, several hundred of them in about 2 dozen sizes. Not uncommon at all in my line of work, we use them daily.
http://www1.mscdirect.com All Amercian made socket head screws are grade 8 unless there SS.

 

Mcruff drilled and tapped in new bolts (aka "studs") into my axle. I had to un-tap the 5 & 7 o'clock bolts and grind down some of the heads so that they'd clear the ball-end of the axle. Pressed/tapped 'em back in, no probs since!

 

OK, for the sake of freindly debate.....

FWIW, I'm not questioning anyone's answers to this point, I'm just naturally curious and like knowing the hows and whys of something before I do it.

What are everyone's thoughts on the strength of the original threaded-into-cast-iron bolt hole vs. a slightly countersunk-enough-to-not-present-any-clearence-problems stud?

I understand the reasoning behind leaving the bolts at 3 and 9, but I'd rather just do all studs instead of 4 studs and 2 bolts just for the sake of continuity. However, I do need to provide clearance. The Vernco site says this....

By no means am I taking his words as gospel, but it is interesting to consider.

What I'm gathering is that if my experience turns out to be similar, I won't have to take much off to make the clearance necessary. I'm interested in other's thoughts as to how much strength I'll sacrifice, if any, by counterboring slightly at 3 and 9 vs. using the original threaded holes.

TIA!

 

Also, are the studs still available, are the part #'s on the tech page still good, and from where? Thanks again.

 

Thad if you want to counterbore the cast bosses in the 3-9 positions, do it. The studs are very tough and you will immediately see why guys grind the back of the stud head instead of the casting. The casting is around .375-.406 thick which is very flimsy looking compared to the rest of the casting. The only reason for doing this at all is to keep from destroying the casting from loose bolts, Alans (hippo) knuckles had almost every hole stripped out.
The studs are still available, Chrysler and thru some NAPA stores.

 

www.sixstates.com

part numbers are still good.

 

You are a gentleman and a scholar McRuff. Your experience is valued. Thanks for the insight!

And thanks to all for the input and answers.

 

Welp, my local Dodge dealer can get the studs....

At $4.80 each. :evil: Do I get a kiss first?

Think I'll look first.

 

google the part number, I think I paid a little over $2 ea

 

Yup! This is the place! Ask for Brian. $1.60 each.