How do you straighten a k-frame off the car? Is it worth it?

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DionR

DionR

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I've got a '73+ V8 k-frame that is pretty rough. Had a LCA tube broken loose and fixed already but yesterday I discovered it is either twisted or one of the legs is bent. Found this by flipping it over and setting the 4 mount points on 2x4's and one is 3/16" to 1/4" off the plane of the others.

How do you tell what needs to be moved? And how do you tweak it once you do?

Is it worth it to even mess with it? Or will it forever be "off"?

Any drawings or dimensions to use as a reference to compare to?

I had planned to get this one gusseted and such and then use it for my Hemi swap. But hate to take a good one out and put in a tweaked one.

Thanks.
 
As strong as they are, without access to a frame rack or some other "strong" device, I don't know how you would. Getting dimensions for the 4 mounting holes is not tough, and they have to be in the same plane If it's much more than that I don't you'll be successful. If you had to pay a guy to put it on a frame rack, it's likely a goner
 
If you managed to bend a K member, I wonder what happened to the car.
My best bet would be to strap it back into the car it came out of and then put the whole car on a frame machine to straighten it out. But like was mentioned above, if you have to go to those lengths, then it might be a goner.

I have a K member I can measure up that came out of a very straight car with frame connectors so I am almost certain it should be straight or at least within factory specs. It is possible that these K members came a little tweaked from the factory because tolerances were so loose. Ive seen countless stories of people here noting that measurements all around their cars were 1/4 inch or more away from factory spec because of loose tolerances.
 
67Dart273 said:
As strong as they are, without access to a frame rack or some other "strong" device, I don't know how you would. Getting dimensions for the 4 mounting holes is not tough, and they have to be in the same plane If it's much more than that I don't you'll be successful. If you had to pay a guy to put it on a frame rack, it's likely a goner
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Part of the trick (in my mind) is figuring out what is bent. It could have one leg bent up or down and the other 3 are fine. Or the whole think could be twisted. Both of those scenarios would give the same results as what I have already done.

Thought maybe the motor mounts could be used to figure out a plane and then measure from that plane. But not sure the motor mounts are even supposed to be in a plane that is parallel to the frame horns.

I found posts by @Jim Lusk where he straightened some, but not sure how other that at least once he cut the thing apart.
 
I mean K-Frame's aren't a rare item.... Is there something special about yours?
 
Projectile Dart said:
If you managed to bend a K member, I wonder what happened to the car.
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The car was beat up, but I don't remember there being evidence of an accident or anything.

Projectile Dart said:
My best bet would be to strap it back into the car it came out of and then put the whole car on a frame machine to straighten it out.
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By now the car is either ingots, holding vegetable or on it's way to being back in the road as a new car. Went to the crusher last fall or late spring.

Projectile Dart said:
I have a K member I can measure up that came out of a very straight car with frame connectors so I am almost certain it should be straight or at least within factory specs.
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I'd appreciate any measurements you could get for me.

Projectile Dart said:
It is possible that these K members came a little tweaked from the factory because tolerances were so loose. Ive seen countless stories of people here noting that measurements all around their cars were 1/4 inch or more away from factory spec because of loose tolerances.
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Good point. I am assuming it is tweaked, but maybe it is on the loose side of the factory tolerance.
 
Cuda416 said:
I mean K-Frame's aren't a rare item.... Is there something special about yours?
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It's a spool mount V8 k-frame. Nothing special to me other than it is out of the car so I don't have to take my car off the road while I gusset one.

There is one local to me, but the guy wants $275 for it. I don't actually see many V8 one's locally, but I don't keep an eye out either. This one came off a car a buddy bought for parts so I kind of tripped over it.
 
DionR said:
It's a spool mount V8 k-frame. Nothing special to me other than it is out of the car so I don't have to take my car off the road while I gusset one.

There is one local to me, but the guy wants $275 for it. I don't actually see many V8 one's locally, but I also am not looking every day either.
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Fair point. Just making sure. I think if it's bent, by the time you got it "fixed", you could probably find one for a decent price. I got mine for a 100 bucks on a trip to CO a couple of years ago. Maybe a parts car for sale somewhere.
 
Cross check frame mount holes with a tape measure.

Bolt it down upside down to the frame/deck of a car trailer. Get an 8' long strong steel lever and a couple of 4x4s and 2x4s as fulcrums and start to lift up any corner that is bent down too far. Out of square push it around with a port-a-power, heavy hoist come-a-longs and chain binders for holding it firm as you push. Can heat areas or cut a few minor reliefs with a sawzall to help things move, then reweld.

Straight and square, now weld the open seams and add a couple gussets where they will do some good.

Good Luck
 
George Jets said:
Cross check frame mount holes with a tape measure.

Bolt it down upside down to the frame/deck of a car trailer. Get an 8' long strong steel lever and a couple of 4x4s and 2x4s as fulcrums and start to lift up any corner that is bent down too far. Out of square push it around with a port-a-power, heavy hoist come-a-longs and chain binders for holding it firm as you push. Can heat areas or cut a few minor reliefs with a sawzall to help things move, then reweld.

Straight and square, now weld the open seams and add a couple gussets where they will do some good.

Good Luck
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Thanks!

Trick is figuring out what needs to be tweaked. It could be a bent leg of the K or it could be twisted.
 
DionR said:
Doubt someone would want to give one away and I don't absolutely need one since I have another one in the car right now.
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. Sorry, wasn’t implying you could get one for free. But, you never know, right?
 
As already stated, the mounting surfaces are all supposed to be on the same plane. Run a straight edge across/between them.
 
pauly said:
. Sorry, wasn’t implying you could get one for free. But, you never know, right?
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All good, just saying that it would have to be a pretty good deal to make sense for me to go look for another one.
 
Cuda416 said:
As already stated, the mounting surfaces are all supposed to be on the same plane. Run a straight edge across/between them.
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Yep, that's what I understood. A straight edge on each leg might say if it is twisted. If each side appears to be on the same plane, then it would make sense that the two sides aren't and it is twisted.
 
Bad Sport said:
Just curious as to which "leg" is bent.
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I can't tell if it has a bent leg or if the whole thing is twisted. So I can't say which leg is bent, if any.

I guess I need to start with ideas on how to figure out exactly what is out of plane. Getting some ideas, but not sure yet.
 
Josh owen said:
I have a 71 slant 6 k you can have. if it's of any help for you at all
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Thanks. It would need to be a '73 or later V8 k-frame to be useful to me.

I do have a k-frame I modified years ago that I could use for sections if need be. Won't work in this project but might be worth the metal.
 
If you tweak it so the 4 mounts are square and to the right dimensions, and can sit "without tipping" on 4 equal blocks on a flat floor, that is likely as close as it needs to be. It is extremely unlikely that if it is bent more than that that you will be able to even move it "straight."
 
Follow up, I have my pre-1973 k frame (biscuit style, not spool) set up on equal 4x4s and I'm noticing 1 leg sitting about 1/4inch away from the rest
I am personally not worried about it and my plan is to fully gusset and seam weld this k frame. I am certain that these cars have enough adjustment everywhere to be able to take care of that in the car to make it a safe street cruiser. I don't plan on ever hitting 200mph in it

I hope this helps!
 
Projectile Dart said:
Follow up, I have my pre-1973 k frame (biscuit style, not spool) set up on equal 4x4s and I'm noticing 1 leg sitting about 1/4inch away from the rest
I am personally not worried about it and my plan is to fully gusset and seam weld this k frame. I am certain that these cars have enough adjustment everywhere to be able to take care of that in the car to make it a safe street cruiser. I don't plan on ever hitting 200mph in it

I hope this helps!
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Interesting. Seems like the same measurements I am seeing on my k-frame.

Sounds like maybe I am worrying about nothing.
 
Once it’s bent out of shape and you bend it back, the bent part will be a weak point. I would just look for another one. $275 is not that much if its in good shape. Start out with a good one, weld it completely and gusset it.
 
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