“I have 2 850s and both are lowered. On my turbo I cut the springs about a coil and a half to get the ride level I was shooting for. I run my cars on the track at Phoenix International Raceway and a stock 850 is a terrible handling car. I ended up cutting the rear springs even more than the front to get the car to sit level. The reason for this is when entering a corner under braking the front end would drive causing the back to come around. I had the only front drive car with an over steering problem. I finally ended up buying 260lb stock car springs for the back.
On my 850R I purchased H&R Springs from the Tire Shack for $214. They were much easier to install than the cut springs and the ride might be a little better.
Bottom line, lowering your car makes it handle noticeably better which is why you would do it in the first place. On the other hand they ride very poorly at slow speeds.”
You want facts.
FACT: Shortening (or purchasing shorter springs) reduces suspension travel.
FACT: Removing coils has a slight effect on increasing the effective stiffness of a spring.
FACT: Overlowering will throw suspension geometry out of whack.
FACT: If you don’t want to bottom out the suspension, possibly damaging shocks and/or other components, under hard compression, you need to increase stiffness as you reduce suspension travel.
Why do you want to lower the car? How much do you car about form over function? If you just want to dump the car to make it look cool, and don’t care about how it handles, and that you’ll have to crawl over large bumps, just go and lop a few coils off. If you want to lower the car to increase suspension performance (lower CG = less body roll), I would advise purchasing shorter, stiffer springs, and get shocks that can handle the shortened suspension.]
And if you do go with cutting, remember that heat will soften springs, so if you use a torch, be careful not to heat the springs.