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K-Frame Compatibility Question

GUMM B

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Believe it or not, the K-Frame of a 1973 V8 Challenger or Cuda has the same part number (P/N: 3583 074) as a 1971 B-Body non-hemi V8 car. What other years of B-Body cars is this K-Frame compatible with?
 
62-72 B body, 70-74 E body.
Essentially the same piece. With differences here and there of course.
 
Okay, and why do you think the 1972 B-Body and E-Body K-Frame part number is different than the one for 1971?
I believe he is just saying '72 B-body is the only other it's the same as since '73-4 b-body is a COMPLETELY different animal...
 
62-72 B body, 70-74 E body.
Essentially the same piece. With differences here and there of course.
The K-member will physically bolt in to any of these, sure. The angle of the steering box is different on E-bodies. '65 and earlier sit the engine a couple inches further forward. There are at least 3 different sway bar designs. Three different families of motor mounts with different positions for different engines. There are probably 12-15 different K-members to fit all variations of those cars.

71-72 B and E body are going to be the best fit for the OP's unit...
 
I believe he is just saying '72 B-body is the only other it's the same as since '73-4 b-body is a COMPLETELY different animal...
curious as to the difference between a 72 & 73?
 
On 73 B bodies went into the isolated K members like big bodies. This made a different frame rail heights and provision for the UCA welded straight to the K member. Not anymore UCAs on frame rails.

Aside the spool engine mount design upgrade.
 
On 73 B bodies went into the isolated K members like big bodies. This made a different frame rail heights and provision for the UCA welded straight to the K member. Not anymore UCAs on frame rails.

Aside the spool engine mount design upgrade.
thank you, I was always under the impression the 72 to 73 changes were purely cosmetic. I had no idea about the differences in frame heights. I would assume all front inner structure component pieces are also not compatible due to this?
 
70-72 versa the 73-up frames

K frame BE replacement 1.jpg


K frame BE replacement 2.jpg


K frame 73-4B BB 2.jpg


K frame 73-4B BB.jpg
 
thank you, I was always under the impression the 72 to 73 changes were purely cosmetic. I had no idea about the differences in frame heights. I would assume all front inner structure component pieces are also not compatible due to this?
Correct. Nothing of the front suspension, front clip frame and steering system is interchangeable. Not even rear crossmember for T bars or T bars

Front valence and fenders are also different although somehow fit. Front bumper brackets diff too.

Some ppl consider the 73/74 as a 3,5 gen.
 
Correct. Nothing of the front suspension, front clip frame and steering system is interchangeable. Not even rear crossmember for T bars or T bars

Front valence and fenders are also different although somehow fit. Front bumper brackets diff too.

Some ppl consider the 73/74 as a 3,5 gen.
Glad I asked and more so for your clarification. I’m looking for a used OEM torsion bar for my 73 and this information will streamline my search.
 
thank you, I was always under the impression the 72 to 73 changes were purely cosmetic. I had no idea about the differences in frame heights. I would assume all front inner structure component pieces are also not compatible due to this?
Dead Dodge Garage on YouTube has a series on the "tool box" Charger and he has videos showing the differences and how to "suck in" the bumpers on a 73-74 to make it look more like a 71-72. Also some good info on making the hide away headlights work of you're interested in that...
 
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