rear coilover spring rate selection 71 a-body

[looter]

Hi guys,
I'm a little bit lost in trying to select spring rates for my 71 monte.
I just bought the bolt in QA1 coil over kit and they come with a 14 inch long 175lb spring.
first problem, even with the coils all the way at the bottom the car sits far too high.
I have approx 5 inches of rod exposed(hehehe) so I'm confident I can go much lower.
I have 550lb springs in the front which were an autocross spring rate according to qa1.

I can likely go to a 7 or 9 inch coil height, but I'm a litttle lost on the rate I should be using to match up with the fronts.

any help is greatly appreciated.

[exwestracer]

The rate sounds about right...in the ball park anyway. What is your spring installed length (top perch to bottom perch) and eye to eye length on the shocks at ride height?

Also, how freely does the axle move up and down with the shocks disconnected? You and a friend should be able to pick the axle up off the jack and move it all the way up and down VERY easily.

[looter]

I have all brand new UMI arms and since the frame is bare, I'm able to lift the frame and it seems to articulate easily.
I'll get an eye to eye measurement.
since I want a low ride height, is there a danger to running the shock in the lower few inches of it's travel as long as it isn't bottoming out?

[exwestracer]

Wait, you said it's a bare frame? Did you have the full vehicle weight on it when you saw the ride height was too high?

We typically try to set the shock at 50% at ride height. No, it shouldn't pose a problem IF, as you said, it isn't bottoming out. Don't forget to check the spring perch installed height with

[looter]

Thanks for your input,Ray.
Very much appreciated