To roughly calculate spring rate
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C63
To roughly calculate spring rate
I was thinking that if there is weight and distance then it can roughly calculate the spring rate of the suspension without taking them apart.
For example, frst measure the ground clearance on the rear part of the side skirt close to the rear wheels. This is the initial measurement. Put some heavy weight( i use my body weight) in the trunk and measure again and see how much it has lowered. If 1/4 inch has decreased with your weight in the trunk, multiply it by 4 to get a rating per inch. So if 200 pounds is added to the trunk, and the drop is 1/4 inch, 200x4 is equal to 800 pounds. Since the weight is distributed to both rear suspensions, divide this weight by two. That would be 400 pounds/inch spring rate for rear suspension. Of course disregarding that the front suspension will have an effect of the weight distributed.
Another way, would be to jack car of the ground. Put a scale under the wheel and rest it on the scale so that it wont add any weight or just reset the scale to 0 if the scale is off, to get the initial measurement. Lower the car by half inch and see how much weight it added. If is 200 pound, then at 1 inch would be 400 pounds.
i did this and got something in between 416-523, since the measurement aren’t really acurrate.
For example, frst measure the ground clearance on the rear part of the side skirt close to the rear wheels. This is the initial measurement. Put some heavy weight( i use my body weight) in the trunk and measure again and see how much it has lowered. If 1/4 inch has decreased with your weight in the trunk, multiply it by 4 to get a rating per inch. So if 200 pounds is added to the trunk, and the drop is 1/4 inch, 200x4 is equal to 800 pounds. Since the weight is distributed to both rear suspensions, divide this weight by two. That would be 400 pounds/inch spring rate for rear suspension. Of course disregarding that the front suspension will have an effect of the weight distributed.
Another way, would be to jack car of the ground. Put a scale under the wheel and rest it on the scale so that it wont add any weight or just reset the scale to 0 if the scale is off, to get the initial measurement. Lower the car by half inch and see how much weight it added. If is 200 pound, then at 1 inch would be 400 pounds.
i did this and got something in between 416-523, since the measurement aren’t really acurrate.
Last edited by Rick X Joaquim; Aug 27, 2019 at 02:37 PM.
