Almost 2 years ago when I first got my M3 I said that my first 'big mod' would probably be a big brake kit to fix the less-than-ideal single pistons that BMW decided to fit to these cars from the factory. However, a little less than a year ago I fell victim to a fate as old as time (maybe): "Electronic Damping Control Malfunction".
I was able to narrow down the issue to a fried control module, and after dozens of failed attempts to re-flash and initialize the EDC module, I gave up and kept driving the car pretending that I never had EDC in the first place. Eventually I got tired of this and so instead of doing the rational thing and replacing the EDC module with a new one and coding it into the car for a lot less money, I convinced myself that it made more sense to abandon the EDC entirely and move to a more dedicated coilover setup with some clicky knobs to control damping instead of a computer and weird electron thingys.
I decided to go with a setup based on the Ohlins DFV Road and Track dampers, however with stiffer springs in order to accommodate wider, stickier tires in the future. I figured that I would end up with wider wheels and tires sooner than the dampers would need their first rebuild, so I opted to go for the revalve now and just deal with the stiffer ride for the meantime even if I dont need it yet.
The spring rates to use were a point of deliberation for a few weeks, and after numerous calculations for wheel rate, travel, grip, etc. I decided to go with 500 pound front springs and 800 pound rear springs. I later found out that these are also the exact same spring rates that the M3 GTS uses, which made me feel even more comfortable with that choice. I think that with the range of damping adjustment on the Ohlins, these rates will provide a nice middle zone between street car/mountain road driving and track-ready performance depending on where I set damping. To accommodate these spring rate changes, I ordered the dampers via Precision Sport Inc. in Sonoma, CA, where Jayme was a huge help in the ordering process. PSI revalved the dampers according to the spring rates I'll be using.
Lastly, I ordered a set of Ground Control Street camber plates to allow for more camber adjustment. I have the alignment pins on the stock shocks removed already and camber maxed out as far as it can go, and I still wear the outside of the front tires way sooner than the rest of the tread even with my mix of 80% daily driving. I know for certain that without more camber, I would be absolutely melting my front tires with the added performance of the Ohlins.
PSI also surprised me by including a printout of my shock dyno graphs, which I didn't even ask for - Shoutout to fantastic attention to detail. You can see that the shocks are relatively digressive and changes in the clicks translate to real distinguishable changes in damping force. You can also see Ohlins' DFV system at work, with adjustments having a small change in compression damping force as well.
I can't wait to get these shocks on the car; planning to do so this coming weekend along with a stud conversion and some spacers so that (hopefully) my fitment doesn't look goofy when the car gets lowered a little. - Check back in after this weekend for another update of the install process and some first impressions! Cheers.