I found a slightly used set of H&R Sport Plus springs in the classifieds and installed them last week (my installation DIY guide is here: http://billswebspace.com/M3HRSpringInstallation ).

The Sport Plus springs are stiffer than the Sport springs but have the same lowering spec- H&R has relabeled the Sport Plus P/N as Race since Turner Motorsports introduced them.

The installation was EASY, only took about 2 hours and was not at all complicated- easiest spring swap I have done.

After reading some reviews on some of the forums I was expecting it to ride like the Flintstones car but surprisingly I found the ride to be about the same as stock, maybe a bit more firm but nothing drastic. I could still tell a difference between the EDC modes and the OE dampers seem to be fine with the increased spring rates.

Cornering and turn in is MUCH improved over OE I'm completely happy with the way the car drives now and how the new springs work with EDC. If I didn't have EDC I might have opted for coilovers but this is the family/wife's car so it works well enough.......

I also pulled the factory strut alignment pins and was able to get ~-1.5 degrees of camber up front, the rear is at -1.8.

 

Very nice lowering job! I'm getting the Eibachs though as the dealer here is a friend. Did you change the bumpstops to the E36 models to regain some travel?

 

I did not change the bump stop or shave the strut bearing/upper spring pad. The OE bump stop is progressive and designed to be part of the travel, I thought I would try it "as is" first and then if deemed necessary later, add the E36 bump stops and shave the spring support like Dinan does. It seems to work fine with the OE bump stop, more drive time will tell.....

It would only take about an hour to make the change......

 

Very nice drop! Should come from the factory this way!