Shack flip / axle move / measure leaves

[hillbilly deluxe]

I am working on installing my ORD shacke flip right now. I know this is going to change the pinion angle quite a bit, but is it also going to cause the axle to be further forward? Since the spring pivots from the front spring hanger it must move forward a bit. I also have some zero rates from ORD so I could move the axle rearward to compensate. I thought about just moving it back anyway but kinda doubt 1.5" is going to improve my departure angle noticeably.

Also, I'm going to do some 52's up front. How do you measure the leaves? I found 3 or 4 different lengths (maybe...) of rear springs on a variety of old chevys while at the junkyard.
Thanks!

 

[Underpowered]

springs are measured center of eye to center of eye. i think it is unloaded.

52's should be pretty easy to find

 

[throttleissues]

The measurement is supposed to be along the leaf so that it would be eye to eye if the leaf was flat. It's pretty easy to pick them out, since the 52" springs are 26" on each end and 56" springs are 26" on one end and 30" on the other.

 

[BGKYK5]

With my DIY4X shackle flip swapped side to side and 56" leaves (long side backward), my pinion angle went from 3* up to 15* up and the axle moved forward maybe 1/2".

Leaf springs are measured along the leaf.

 

[hillbilly deluxe]

Thanks for the info. That helped me to decide to move it back a bit.

Now I'm positive I got 52's from the junkyard. They were off an '84 half ton pickup. I liked that they had the teflon pads at the ends of the leaves and they looked in good shape. There were some 70's blazers but I didn't like the look of those springs near as much.