I.D. The difference in LA to B body K Member

[Shorty Thompson]

Can someone tell me if this is a Big block " B " body K-member. Working on a 1973 & 1974 Plymouths;

 

[Cop car wagon]

Thats a nice part. Hard to find one with sway bar tabs.
The difference is on the motor mounts.
Big and small fit the same K.

 

[Shorty Thompson]

Thats a nice part. Hard to find one with sway bar tabs.
The difference is on the motor mounts.
Big and small fit the same K.

With all due respect. That K'-member is bent & twisted as well as broken in a couple places. Had I see that before bought it, I wouldn't bought it. As far as the sway bar tabs, I'll cut them out and weld them on 1 that's not bent and twisted. Thank you for help.

 

[Kern Dog]

Thats a nice part. Hard to find one with sway bar tabs.
The difference is on the motor mounts.
Big and small fit the same K.

I don't think you're right on that. From what I read, after 1972, there were different K members for each engine family. The main differences were the shape and placements of the motor mount pedestals.

 

[70 sublime]

I have this one out of a 73 318 Charger that I took out and had sand blasted to swap into another 73 charger that was a slant 6 car
Car got sold before I got around to doing the swap
Too bad you are so far away
I can measure anything you want to compare on yours

 

[Shorty Thompson]

I have this one out of a 73 318 Charger that I took out and had sand blasted to swap into another 73 charger that was a slant 6 car
Car got sold before I got around to doing the swap
Too bad you are so far away
I can measure anything you want to compare on yours

View attachment 1711822

View attachment 1711823

View attachment 1711826

View attachment 1711828

Gawd I wished you were wrong, but I really think you're right. I got 1 out of a 73' now and they almost identical. Aside for the sway bar mounts.

 

[Cop car wagon]

@Shorty Thompson
There is no way, from a picture to tell if its bent. Thats on you.
Kern, its 37588 to 136. You win.

 

[YY1]

I believe all 73 and 74 B body cars except WL and RL got front sway bars.

Yes the mounts are different between big and small block.

75-78 BB K frame is a direct swap.

They sold a LOT of 400 powered Cordobas.

...and they all had sway bars (and the larger BB spec bars to boot).

 

[Kern Dog]

Kern, its 37588 to 136. You win.

 

[Cop car wagon]

Thinking is not knowing.
I've had and have several.
And I've been suspended for truth telling.

 

[Kern Dog]

Are you referring to post counts on the forum?
Someone with a higher post count can still be wrong, myself included. I've never owned a 71 or later B body so I have no firsthand experience with their K members. I thought that the K members were different for slant six, 318/340 and 400/440. An article in Mopar Action did state that. Their tech editor was a pretty sharp guy.

 

[Cranky]

Used to be everyone said the small block vs big block K frames were different while it turns out that you only had to change the engine mount brackets and that was it. I actually still have an old magazine that says you have to change out the K frame from a small block vs a big block and I found out in the mid 70's that was wrong. Thing is, I have no idea about the later K frames. Just can't believe ChryCo would spend the money to make the K's different for each engine family because that's expensive for the manufacturer......

 

[Cranky]

Are you referring to post counts on the forum?
Someone with a higher post count can still be wrong, myself included. I've never owned a 71 or later B body so I have no firsthand experience with their K members. I thought that the K members were different for slant six, 318/340 and 400/440. An article in Mopar Action did state that. Their tech editor was a pretty sharp guy.

The /6 K had totally different motor mount stands than any of the V8 cars....

 

[Kern Dog]

That was one of the dumbest Mopar ideas that I can imagine. All the engines needed specific mounting brackets anyway, so why didn't they have a common K member? The early A bodies had it that way. I learned before I bought my Charger in 2000 that it was available with either slant six, wedge V8 or Hemi K members.
Why all the different K members?
For that matter, I've often wondered why the automakers had post sedans AND hardtops. Why? Now you have to have special tooling to stamp out different roof sections, C pillars, door frames are different, glass is too. Why not pick one design and use that? What did they gain by making two versions?

 

[Cranky]

That was one of the dumbest Mopar ideas that I can imagine. All the engines needed specific mounting brackets anyway, so why didn't they have a common K member? The early A bodies had it that way. I learned before I bought my Charger in 2000 that it was available with either slant six, wedge V8 or Hemi K members.
Why all the different K members?
For that matter, I've often wondered why the automakers had post sedans AND hardtops. Why? Now you have to have special tooling to stamp out different roof sections, C pillars, door frames are different, glass is too. Why not pick one design and use that? What did they gain by making two versions?

Depending on the year or the cars, a 'post' car wasn't much different than a hardtop but a sedan was much different. Also, the /6 K had much different mounting stands than all the other cars but the V8 cars were very similar and it was easy to just change the mount brackets for the V8's, small or big blocks.

 

[T2R9]

To answer the OP's question. Yes that is a big block K member. Big block, small block, and slant 6 are all different for 73 and up.

 

[Kern Dog]

Thank you, finally a definitive answer.

 

[T2R9]

The biggest give away on big block vs small block is the passenger mount has a triangle bracket on the big block and an L shaped bracket on the small block.

 

[Cranky]

The biggest give away on big block vs small block is the passenger mount has a triangle bracket on the big block and an L shaped bracket on the small block.

View attachment 1712091

Are there any 'brackets' that will allow a big block to be mounted to a small block K?

 

[T2R9]

Are there any 'brackets' that will allow a big block to be mounted to a small block K?

Schumacher used to make a set.