67 Big Block K-frame Reinforcement

-

matthon

Well-Known Member
Joined
Aug 29, 2008
Messages
2,963
Reaction score
1,319
Putting up a few pics and questions.
I've searched and unfortunately unable to locate good info on bb.

Firm Feel website lists reinforcement kits for 62-76: Firmfeel Mopar Suspension and Steering
There is 1 picture each for 63-66, 68-72, and 73-76, and all appear to be small block.
No mention of big block, and the pics leave out 67, probably just a typo.

I called them and was informed they have a big block kit, it has 1 more piece than the small block kit which has 5, but didn't know what it was at the moment.

The 5 pieces are, 2 big washers for the lower control arms, 2 washers for the strut rods, 1 piece to box in where the steering box mounts.
6th piece for bb unknown.

I asked if the kit came with instructions or a diagram, they said no but they write on the pieces and there are illustrations on the website with all different angles.
I only found one page, 3 pics as mentioned above.

Although none of the pics apply to me, it's not rocket science.

I do believe the sb and bb k-frame might be different in how the steering box mount is welded on to the k-frame.

Reinforcement Kit
They said it includes 5 pieces, 1 extra for the bb.
If there are 4 washers, 1 steering piece, and the website lists 1 skid plate, that's 6 or 4 'pieces' depending on how you look at it.
What really comes in the sb kit?
What's the extra bb piece?

The 68-72 sb pic on their website, shows what appears to be a reinforcement on the front of the driver side engine mount.
Does the sb kit have the 6th piece, or is that factory?

LCA
My understanding is the washers to reinforce the LCA pivot holes go on the side the LCA comes in on, the rear, not on the nut side, the front.
I guess that makes sense as you want the full thread of the pin to stick out, but it makes no sense as the LCA tube is clearly welded to the k-frame at the rear, and not the front.
I've read on fabo that some cut the frame open to weld the front of the tube to the k-frame, which leads me to believe it's not welded from the factory.

Wouldn't one want to reinforce the front?
If so, what's the best method?

Strut Rods
My understanding is if you use an aftermarket strut rod, like QA1, you don't need, or can't have, the strut rod washer from the reinforcement kit welded on, is this correct?

Steering Mount
I haven't had success in locating good pics of the small block k-frame steering mount, but the sb and bb are clearly different here.
The bb steering mount appears to have much more support due to the placement of the engine mount. On mine, not only is it welded to the k-frame all over, there is a plate that supports the mount that is also welded to the back of the steering mount, see red arrow, and blue circle shows penetration of weld.
The second pic of the steering mount shows the plate again, red arrow, and the area where the piece from the kit goes, blue circle.

Does anyone know if I have the placement of the kit piece, blue circle, correct?
If so, I'm not seeing the benefit to adding it, at least on the bb k-frame.

Idler Arm Mount
Nothing to do with the reinforcement kit, but just to note, I thought I recalled some reinforcing this but couldn't find any examples.
It appears to have plenty of support and welds.
Personally, not going to change it to 68-up mount.

I know some 'fix' the factory welds if needed, and weld the seams as well.
I don't believe any of the existing welds are horrible, maybe not pretty, but nothing that needs attention. No cracks or bends, level, just dents on the bottom.

I don't like the LCA tubes hanging in the front, if that's the case, and I could see welding the seams.

Thank you to anyone who reads this book and provides feedback.

20201125_190957.png


20201125_162132.jpg


20201125_162126.jpg


20201125_175736.jpg


20201125_180347.jpg


20201125_161839.jpg


20201125_190853.jpg


20201125_180200.jpg


20201125_172927.jpg


20201125_172959.jpg
 
Last edited:
Factory BB k members are already reinforced. 1967 was also different in that the idler arm bracket was different type (one of your pics shows a 1967). Rear spring pockets were also reinforced on BB cars. I have a 1968 factory BB car with engine out if you need pics.
 
Weakest area on a 67 is the idler arm mount, should be a kit to make it a 68-up sandwiched idler area IMHO...
 
Idler arm bracket on the 1967 only supports the arm on the bottom allowing the arm to twist out of alignment. The 1968- bracket holds the arm top and bottom- no twist.
 
67 idler arm bolts into the mount from the bottom.
I've read about the concern over the 67 idler arm mount, and I understand it, yet I don't.

The section it bolts through is quite thick, I don't see any visible wear on the arm on it now or the one I removed years ago, but just a visual inspection off the car.

Also, wouldn't all the joints in the steering be susceptible to the same issue as the idler arm, as they are all bolted on the same way?

Anyone ever try to mount a 68 idler arm and just weld a plate on top?
Here are some good pics of the differences.

383 motor mounts, Form S

20201126_134119.jpg
 
Looks to me like there is no support for the front of the LCA mount/pin. Tube not welded to k-frame at all.
Even the reinforcement kit doesn't address this.

Why is this ok?

20201126_140405.jpg
 
The LCA tube is welded on the inside, but the weld is more of a tack. The Firm Feel kit is crap, as far as I'm concerned. Pieces don't fit well and some seem to have no purpose. It's not that hard to make your own.

For the pin tubes, I cut access on the bottom of the k-member and weld them from the inside. You can also look for cracks in the tube. These show how much the factory welded them in. I have also added half washers and welded them to the tube and k-member as well as just adding weld to the tube.
20160416_122415.jpg
20160418_194628.jpg
20170122_145711.jpg
20170122_153452.jpg
 
My son's k-member. Missed this completely when I built my first big block a-body (this is the k-member that I used in my car back in the 1990s). This was somebody's "fix"...The last pic is the pin tub out of the k-member. Yes, I have a jig that allowed me to get the tube back in the correct location. I don't have pics of the finished product, but it works now...

This sort of stuff is much more important that a few gussets elsewhere. I also have a jig that allows to see how square the k-member is. I have actually fixed one that was bent pretty good, but I had to separate the upper and lower half.
20180911_142529.jpg
20180911_142601.jpg
20180916_132039.jpg
20180916_132050.jpg
20180916_132109.jpg
20180916_144626.jpg
20180916_144633.jpg
20180916_144642.jpg
 
For the pin tubes, I cut access on the bottom of the k-member and weld them from the inside. You can also look for cracks in the tube.
Nice, thank you.
Never thought there could he cracks in the tubes, so I'll check.
I have also added half washers and welded them to the tube and k-member as well as just adding weld to the tube.
Did you add the washers to the inside once cut open, or to just the outside?
 
I was also thinking that adding additional spot welds to the perimeter couldn't hurt, and found this on fbbo today:
B Body K member Best Upgrade

After considering a few things, cutting an access hole to weld the sleeves from the inside, adding additional spot welds around the perimeter on the bottom, possibly welding the seams, and dents in the bottom, which I pulled out slightly with a slide hammer through the bottom 2 holes, my brain asked -

How realistic it would be to separate the 2 bottom pieces completely?

It appears to be welded well in all 4 corners, and I don't want to remove the idler arm mount and screw it up.

I think the correct answer is address the sleeves by cutting access holes.
Then, see if I can cut the bottom out only where the dents are if there are not too many spot welds.
Add additional spot welds to the perimeter and call it done.

This isn't a track or race car, but it's out, all apart, and I'm putting in new suspension stuff.

Pics are before slide hammer, but even with the biggest washer I could get into the k-frame, and also working it with a steel dowel from the top holes, and a little heat, it's just too thick to move back into place.
Of course, what the heck do I know anyway.

20201127_014115.jpg


20201121_170634.jpg
 
I added washers to the inside of one k-member. I don't think it's really necessary if you just add weld around the tube.

Separating the two halves is A LOT OF WORK. Lots of spot welds and several places of mig weld. I did because the k-member I was working on was tweaked bad from an accident. I bought it to find out IF I could fix it. I felt that there was no way that it could be straightened as a complete unit with the tools that I have.
DW213178.JPG
DW233202.JPG
DW233203.JPG
DW233205.JPG
DW233206.JPG
 
Thank you Jim, I appreciate the pics very much, and the info.
That is tweaked alright, and I have no desire to separate at this point.

I'll keep it simple, I'm no master welder or fabricator but I'm sure I can stick to my short plan I detailed above, and maybe add washers to the exterior.

I will never jack the car up using the k-frame, but this thread makes me wonder if there is any benefit to bracing between the upper and lower sections?

I have no interest in pursuing such a modification, but it does appear the 2 lower holes line up with 2 of the upper holes.
If I was developing a reinforcement kit, I would test welding in tubing between them, top to bottom, and adding one in the middle, and see if a jack would just push the top layer out of wack.
At the least, putting tubing in those holes would prevent the majority of oil and fluids from draining into the k-frame, maybe.

Ok, thank you fabo. This began with adding new upper amd lower control arms, sway bar, etc. Grew into a might as well pull the k and clean/paint, to another might as well ask questions and address some issues.
Now the work begins.
 
As a unit the k-member is plenty strong enough to support the weight of the car when jacking. Any damage you see on a k-member occurred while bottoming out.
 
i have a place by me that does chemical stripping. well worth the $75 to have them soak all the old crap out of the K before trying to weld on it. i also ground and re-did out some of the worst of the factory welds and just generally cleaned it up.
DSC01511.JPG


cut my own plates from 1/8", and anywhere there is a gap from one bracket to the next, welded in more bracing. i also cut back the inner seam since i'm planning to go to an aftermarket oil pan, and re-welded it all the way around. added "washers", that are just 1/8" plate, to the strut rod holes and completely forgot to open up the cavity and weld the inside of the tubes. i'll be correcting that next year when i have it all out for the motor swap
 
Wow, that factory weld looks horrific.
Mine all look very good, nothing like that, with plenty of penetration, I'm no expert though.

Got it done today.
I recently bought a decent welder, got rid of the flux core, so it is the best I can do right now.

I put the LCA pins in before welding.
It was a little challenging to weld inside, but I'm pleased.
Based on the research I've done, my concerns, the feedback here, I think it's the best improvement I could make.

20201129_145513.jpg


20201129_162114.jpg
 
-
Back
Top