A couple coilover Q's

[trailblazr81]

OK Ive done some reading about coilovers and have a couple questions. If a 800 lb. coil spring has a wheel rate of about 200lb. Then the coilover should be about 220lb. Then wouldnt the 300-350 lb. spring recomended for street use with some auto-x/ or road racing be on the stiff side? Also how does the spring length affect ride or performance? Say a 10" 300lb. spring vs. a 12" 300lb. spring?

Thanks guys!