Rebuilding LemonWedge.

[RemCharger]

Happy New Year to all! Hope you all had a fun and safe celebration.

Hernia surgery and holiday family time has slowed progress with the car some. But I got back out in the garage for a short time today. Stripped the suspension off the bent K-member, and in the process came across a discrepancy between my original and the donor K I sourced. The idler arm mount is different between the two. The donor K-member is supposedly out of a 70 383 Roadrunner. Did the idler arm assembly change between 67 & 70?
What’s my best path to tackle this variable?
see pics; original frame black. Donor Blue.
My idler arm does not fit within the boxed mount on the new K-member.

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Shouldn't be hard to locate the new style idler arm.

 

[malex]

I run the same K frame in my 64. It’s from a 69 Runner.

 

[LemonWedge]

Shouldn't be hard to locate the new style idler arm.

I guess that answers my question. Shouldn’t be an issue then.

 

[LemonWedge]

the Blue is a late K , 66/67 on ? With idler arm mounted between ears and bolt through . More secure and easier idler to buy .
Looks like original was a early K frame - idler arm has pin at each end ?
If so the blue K will move motor back due to change in mount position .
My understanding later k bolts same spot uses same linkages bar idler arm .
PS : guess you will be pushing firewall back and modding crossmember to suit . And prob shorten tailshaft . Oh joy ;-(
Tex

I suppose this is how we learn. Everything I read said the K-members were the same…. Apparently not (?). If there was a change in engine location, it must not have been much. Both Hooker and Doug’s list the same headers for both 67 & 70 B-Body vehicles. For what it’s worth or applies here, my car was built in late 66.

The good news Tex, is that my plans include a motorplate. So the K-member won’t dictate engine location.
One of my racing buddies loaned me his plasma cutter; I’m going to take this K-member to the surgery room anyway, the only mounts left when I’m done will be the steering box and idler arm.

A quick Look at Summit identifies Moog P#K7041 for a ‘70 roadrunner, which the K-member is supposedly out of. Looks correct, will be in my next Summit order. Looking at the two designs, the captive bolt through design would appear to be the superior design, especially for a car that will be picking up and setting down the front suspension regularly.