Customs 3 inch drop and slams hard...need tech help

We're saying the same thing. As you wrote, the more a shock leans, the less stroke it will have for a given magnitude "bump", so the less damping you get. Therefore, to compensate, the shock must be stiffer to provide the same damping as a vertical shock.

 

I wont swear to the percentages having blanket accuracy when involving progressive rates but the premise is accurate in the relative way pictured.


This concept can be used to allow greater suspension travel than the designed coilover or shock stroke.

 

Ray.
The shocks valving is increased in proportion to the motion ratio [squared] to compensate.

The 2 main advantages of leaning them over
One:
Is to lower the piston speed per inch travel [motorcross bikes do this]
Excessive speed/travel causes heat to expand the inner tube and fluid bypasses the piston/valving and also aeration of the fluid on twin-tube designs.
Two:
Is to create a rising rate of stiffness during body roll. As the car is leaning over, the outside shock is more perpendicular to the compression loads applied to it .
So the normally "over valved" shock has a reduced motion ratio. [ a motocross bike with laid down shocks at full compression is a good example]

On modern racing cars , they reverse the motion ratios so the shocks travel is more than the suspension travel.
This is because a shock isn't damping until the valving is bounced at least 0.060" off the seats.

 

I am dancing with the more knowledgeable here but is there a chance the position of the Yoke on the 9" versus the OEM rear is off center putting the driveshaft in collision with a tunnel designed for a centered yoke?

My apologies if this was already noted...In field learning is definitely traditional...not good, but traditional and I'm confident we will get to the bottoming out of it...

 

Once we get some better pics ,,,,
Anything is possible and there’s probably a really good reason the modification was done and then sidetracked for a dozen years.

 

Jellyfish?

 

Ya I had same problem. previous owner put 3" lowering blocks in my '60 Ford. This winter I noticed the casting over the drive shaft hit the floor. I cut the blocks down to 1 1/2" to raise it. We'll see how that goes.

 

McGee's axiom- Some is good, more is better, too much is just right.
One inch, two inch and three inch blocks.
When mounting shocks that are leaning the studs or bolts must be parallel to allow them to pivot properly. In the pic, the one on the right is right. The one on the left is wrong.

 

The OP hasn't been back since WEDNESDAY LOL.

 

It looks like the upper shock mounts are still there and ok so all you'll need to do is scrounge up some bottom spring plates with shock mounts that will line up with them when the car is on the ground. Or you could make a bracket from 1/4" plate and weld it to the bottom of your spring plates. While it's on the ground measure the distance from the upper shock mount to the lower, you will need shocks that are that length when they are in the middle of their stroke.
I also think you will be better off with 2" lowering blocks, they will help all of your interference and you'll hardly notice the difference in the look. My '56 Chevy came to me with 3" blocks and everything was hitting everything, even the driveshaft was jammed into the transmission. A simple change to 2" blocks fixed most of the problems.