"I'm unclear on the way springs affect ride & handling compared to shocks & struts. What's the difference in ride and handling with stiff springs but soft shocks, compared to stiff shocks but soft springs? Which setup is more performance/handling oriented, or would I want both springs and shocks to be stiff? I rarely race, but enjoy very high performance ability on the road."
The differences in handling can be described as follows: Shocks/struts affect dynamic or transtional handling. For example, on a slolom course, or when you first hit your brakes, or when you first start into a turn and the weight is transitioning to the outside wheels, etc. In other words, whenever the suspension is moving. After the suspension stops moving, you get into static or steady-state handling which is affected by springs and sway bars. For example, on a skid pad, or in the middle of a long sweeping turn. There is a lot of overlap, but the above is true in general. As far a ride quality, both springs and shocks can affect ride harshness similarly. Stiff springs/soft shocks will cause the pogo effect over bumps. The car will transition weight fore/aft and side to side much faster, and with less control. Soft springs/stiff shocks, IMHO, provides a much more controllable handling setup. Weight will shift more slowly and controllably. The danger here is that if the shocks are too stiff, the suspension will not handle washboard bumps well. Of course, this arguement can be made for the other configuration as well. The soft shock setup allows the suspension to move too much, the stiff shock setup doesn't allow enough movement. Hope this helps.
From: Billy Moore
"As you may know, checking them is as easy as pushing down on each corner of the car to do the bounce test. Bounce it up and down, and then suddenly let go. The car should go up and down once, then to the final resting height. A small amount of movement thereafter is ok, but excessive movement means new struts/shocks are due."
The 'bounce test' is the method used by the shock dealers to test the car; it is a very poor way to test the shocks. My cars have passed this test; after removing the shock or strut I found the reason: while the compression damping was completely gone, the rebound damping was fine, allowing the car to 'pass the test' but when driving the car, it would dive, squat, and 'crash' over bumps. This is with only 20K to 40K miles on them.
Aftermarket sway bars (ie Herb Adam's) will hamper this 'test', as each side will not move independently of the other.
The two methods that will show that a shock is bad: detected fluid leakage, and remove and test.
"My 86GT passes this test with 72,000 miles. I drive my car as you stated you do. If you are basically a conservative driver with an occasional desire to push it, the stock shocks and struts, if they pass the test, should be fine."
If this is your driving style, you will probably be more than happy picking up the phone book, choose the biggest ad, and ask em for what's on sale. Throw in a 4 wheel alignment, and off you go...
If firmer handling is your goal, go with the Konis. Stay away from anything advertised as 'nnnnn-a-matic' (ie Monroe GP); these high pressure gas struts/shocks 'firm up' as the movement increases (too late). These are not performance equipment, despite what the salesman or brochure sez. And despite 'lifetime warranties', I've seen passenger-car-grade struts wear out in less than 20K miles. The dealer will then show you this neat 'bounce test' to show you how there is nothing wrong with your shocks...
From: Dave Hewson