K-Frame tolerances..... loose at best.

[brads70]

Thought I'd share this....
So I'm thinking about what to do this winter, planning on a project with a couple of K-frames I have acquired. They are both supposed to be from an e-body?  So I thought I'd compare the two K-Frames I have.  I put the two side by side and started measuring. I found the mounting pad for the steering box varied by 2 degree's 21-23degrees, but the worst issue from a handling perspective was the locations of the steering box pad and the idler arm mount. It varied by up to 1/2" measured from the LCA pin holes. The LCA pin holes them selves were pretty close 1/8" at worst. The idler arms and pitman arm mounts NEED to be right if they are going to line up straight/parallel  when assembled. This could explain "some" of the header fitment issues as well as the nightmare fitment issues of the new Boregson steering box.  Again it could explain "SOME"  of the issues but not all.  Being a moldmaker and getting cranky when things are out by more than a thou this could make one OCD    I assume it's just sloppy production tolerances from back in the day. Don't be too dismayed at Ma Mopar as from circle track racing I've also done measurements like this with Camaro front subframes , they varied 1" at times!
 







Note the differences in steering box pad/gusset placement.

[anlauto]

There you go...over thinking it again Brad

[roadman5312]

    Thats really interesting Brad. We ran into issues on Toxicwolf's car where the center link wasn't parallel. Found a factory bulletin showing how to shim the steering box and/or file out the pitman arm holes oblong to correct the problem. I'm going to do some measurements on the hemi K based on your example here. 

[71gogreen]

Brad, I know what the problem is, you tape is worn out!

[CudamanTom]

Will someone get Brad a beer please?   

[crash340]

Good stuff Brad, question is, does anyone have a factory engineering drawing on this to determine what it should be or is it best to just try and equal things up as best possible to the individual car etc.

Greg

[ToxicWolf]

This is interesting

http://www.engine-swaps.com/Pages/ProductsType/K-Frames.html

[GoodysGotaCuda]

Good stuff Brad, question is, does anyone have a factory engineering drawing on this to determine what it should be or is it best to just try and equal things up as best possible to the individual car etc.

Greg

x2

On top of all that you have to hope it's square in the car. Unfortunately almost nothing on these cars come even close to today's part variation standards.

[johns cuda shop]

Yup. Very laughable .

[HP2]

Sadly, this is the case with most of them. I think I have had to modify idler mounts and/or shim steering boxes to get the tie rod end locations correct on nearly every mopar I've ever had.

[Jesus H Chrysler]

One was made on Monday, and one on Friday?      Thanks for pointing this out Brad.  I'll have to check my donor K before it goes in the Coronet.

[drewcrane]

They used the special stretch  fit technique,and an old jig

[johns cuda shop]

Trust me no jig was used.. a hand drawn blueprint  and a tape measure .What did you expect with 60s technology . Thats why its so funny. 

[HP_Cuda]

I can see them swapping an engine drivetrain into another body because of these deltas.

I've been bit by the kmembervariances after using a buddys kmember so I would have to swap it out at the time.

Never again