C10 coilover spring rate for autocross

[vet57air]

I have a pro-tour 66 C10, I call it a Cgt. Has a custom frame to my spec to carry its 22's. I built it to handle and have been playing with coilover springs to fine tune the handling/ride height. Problem is from what I have read I am in a little uncharted territory. I started with 650# front springs with 500# out back. The rears are mounted vertically and I find them fine, mind you it is much more than I would expect, but it is not harsh. The fronts with the 650's I had the collars up showing about 2" of thread. They are mounted at about 70 degrees. I bought some 750's and to get my ride height have about 3/4" of thread. Driving the 750's feel much more compliant, not as hard as the 650's. Am thinking of going to the next spring, but it is a jump to 900#. Yes, I have used Ridetech's calculator and my 750 is their "full on racing" weight. Anyone else using spring rates in this range or higher?
209564

[SkinnyG]

My previous daily was a squarebody C10, and I ran 1060lb 1-ton coilds up front and "Big 10" (8?) leaf pack out back. It was firm, but ride quality is subjective.

I recommend learning how to calculate spring rates based on suspension frequency, and chose your springs that way. It's a bit of measuring and a bit of math, but I do all my autocross cars this way and have had very good success doing so.

I'm sure there are online sources, or if you prefer books I can send you links to some. I prefer books - people who don't know what they're talking about are less likely to write a book on the subject.

[CSG]

Do you have the corner weights and motion ratio's?

[vince72]

Nice truck!