"Spring Rates" Help me understand.

[shadowghost1]

I am into stadium truck racing and I am not for sure how that spring rates work. I have a MF XXXT and I was running at my local track and it was not cornering well or coming of jumps to well and a local racer told me to change my 2.3 springs (on the rear) to 2.5 and change my shock oil from 20w (I had it all around) to 35w in front and 30w in back. Now this truck handles better than any truck I have ever driven. Why is that, I dont understand how it works in relation to each other.

[SteveK]

The number is the rate, which means the number of pounds it takes to compress a spring 1 inch.

If you change to a stiffer spring, and keep the same oil, the oil will in effect feel 'lighter' because the stiffer spring will move the piston through it more easily. The overall effect is that the suspension is much stiffer and more responsive: With light oil and springs, the suspension will compress more easily, and the truck will have body roll in the corners.

[-=ADA$=-]

its all true, and also with thin oil and soft springs the car will roll more, and also will be more prone to bottoming out, with hard springs and soft oil, the car will roll less, and will much quicker straighten up after turn, so its more responsive as SteveK said. With thick oil and soft springs, the car will be less responsive, and also wont be as prone to bottoming out. Thick oil and stiff springs will give less roll, less bottoming out, but the car wont handle bumps as good