Originally Posted by biggynuts01
Very good info. Thanks!
So far I've made an assumption on what the rear damper motion ratio is based on it being outboard of the spring (closer to the wheel) and at an angle closer to vertical compared to the spring. With a few simple measurements it wouldn't be difficult to calculate the rear damper motion ratio.
Nevertheless, for a street car, or even a dual-purpose car, I do not see an advantage of running a rear coilover setup over a stock rear setup, especially on a car without a stiffened rear shock tower. On my old e46 M3 after having a custom welded-in roll bar installed I discussed switching to a rear coilover setup with a shop that professionally races BMWs and they said there was really no performance advantage for a "street" car. I know certain people have stated it's "ok" to run a rear coilover setup on the e9x M3 but I bet if the shock tower were to fail they wouldn't repair the damage for free...