427 Cobra rear suspension and Spicer half shafts

[my427cobra]

Tried to post to my old thread from a few months ago, but it may not be working.

So I'll submit it as a newly restarted thread.

This was a great thread. I learned a lot from all of you who contributed as I collected the info I needed to proceed with my IRS scratch build.

To summarize, here are the key specs/dimensions I learned about the 427 Cobra IRS:

Rear Upper Control Arm (UCA) length: 11.4” to 11.5”

Rear Lower Control Arm (LCA) length: 12.4” to 12.5”

Vertical distance between the UCA and LCA at the inner (frame) mounts: 10 to 10.5” (dependent on the UCA downward slant towards the rear for anti-dive)

Rear Upright/bearing carrier total height between the UCA and LCA mounts: 12.35” to 12.43”

Rear UCA mount on the upright to the axle C/L: 6.73”

Rear LCA mount on the upright to the axle C/L: 5.62”

To summarize the rear set-up specs:

Assume a 5” ground clearance (at the rear of the frame) with 15” wheels/27” OD tires

Rear Toe-in: 3/16”

Rear Camber : -1.25 deg

Rear Upright Castor: ?

Rear Anti squat: UCA 3.5 deg (UCA frame mount slopes downward to the rear)
LCA 0 deg

So the only remaining question I have for those that have helped me so far:

What amount of static Castor is built into the rear uprights?

Thanks to all of you who have helped me out with all this info.

Cheers
Greg

[my427cobra]

I have now learned the CASTOR of the rear upright was spec'd as 2 deg negative ( top of the upright leaning towards the front of the car).

I hope to post bench pics next week dependent on my IRS scratch build progress.

Cheers
Greg

[LMH]

Hey Greg, I know back when, rear toe-in setting was 1/8” and 1/2 degree negative camber for Cobra 427’s. That was the specs from SA.
Just some useless info for giggles!
Larry

[my427cobra]

Thanks Larry. I keep saying CASTOR.

I should be saying CASTER of course.

But if I lube it, do I use CASTER OIL or CASTOR OIL?

Cheers
Greg