Instant Center Changes With Leaf Springs?

[aotte1]

1986 C10 SB SS, with pretty much original rear suspension. Have never raced leaf springs, always 4 control arms where you can adjust instant Center (IS) by changing angle of upper bar at diff. Looking for how it is done for pretty much stock 86 C10 with leaf springs.
Thanks,
Les

[Super73]

Lower/raise the front leaf spring mount. IC goes from rear tire center trough the leaf bolt hole.

[aotte1]

Super 73,

Thanks, is it pretty easy with a 1986 C10 rear suspension to tune IC around the center of gravity (CG). The front of truck is lowered about 2.5 inches with front springs cut one coil. I was planning on lowering rear the same amount by moving original rear spring hangers.

Is it pretty easy to get the 86 rear suspension to hook for 12.0s or is 13s more reasonable.

Thanks,
Les

[Super73]

Les,

Put a caltrac set up on it and you will be surprised how fast our can go.

[aotte1]

Thanks,
With the Cal Tracks on leaf springs, it will simulate a ladder bar rear set-up?

Any idea where the CG is on 1986 SB SS with World Products 400 SB ( alu head and intake) is, this leading me to ask how much you raise front rear spring and/or lower rear spring to adjust the IS ( instant center) . Do I also need different rear leaf springs?
Les