try to find the heavy duty/higher quility 4 inch spring. they dont jack your seat all up high and they shouldnt bottom. The quality of the spring and the positioning/angle of the springs will be the main factors. Just get the best quality you can find and make sure they are mounted at an angle which allows them to do their job. If your ass is bouncing straight up and down, the springs should be positioned that way as well.....
H.C.C.M.F. Local 6978
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