I talked to Koni today. The adjustable sleeves can not be used on these shocks due to the fact that the upper spring perch is welded to these shocks. You can send your shocks to be modified, but after the parts and labor to do so it's about the same price as buying new ride height adjustable Koni's. I was bummed to hear that to say the least.
According to the Koni performance rep I spoke with today, who by the way sounded as though he really knew his stuff, there are mathematical formulas dealing with corner weight, preload, and unloaded length to figure the height and rate needed to obtain a specific ride height change.
I used a much more raw method - more like tossing a coin in the air!
Jeff G. got the ride height on the rear of his car exactly right using a 10" 250 lb. rate QA1 spring. However, he gets an occasional rub on a big bump. I used the uber scientific method of determining by rough guess that an additional 25 lb. of spring rate would do little to change the ride height, but may help a bit with the occasional rub over a large bump. I ran my highly scientific guesstimation past the Koni rep when he was done explaining the mathematical way to figure this all out. He paused, thought about my reasoning, and said "what the hell - sounds good to me, give it a shot." 10" 275 lb. springs were ordered today!
