No Eibach for CP cars...

[dhirm5]

I emailed Eibach to see if they were planning to release springs specifically for the CP. Answer came back negative - if we want a further drop with CP, we need to use the same springs as the non CP.

Thoughts on this? What's different about the CP springs other than their height? Guessing it wouldn't be an issue to use the same springs for CP vs non CP.

[dhirm5]

Also - here's Eibach's technical data on their F10 M5 spring set. Eibach uses a progressive spring rate:

http://eibach.com/america/en/eibach-...ro-kit-2013-14

I can't find the specs for the H&R springs, nor even whether they are progressive.

[stealth.pilot]

I don't know why you would want to drop a CP car. The height is perfect.

[Used2be]

Originally Posted by dhirm5

Thoughts on this? What's different about the CP springs other than their height? Guessing it wouldn't be an issue to use the same springs for CP vs non CP.

I wish one of our friendly aftermarket companies would take the time to test the various spring options we have for the M5. Test the stock spring against the CP spring and the two lowering springs available, H&R and Eibach. We don't know if the H&R or Eibach are stiffer springs than stock, but they do lower the car a small amount.

I would hope that the CP spring from BMW has a higher spring rate than the stock spring in addition to the slightly lower stance. You might find that your CP M5 wouldn't be any lower with the H & R or Eibach springs. I haven't ridden in an M5 with either the H&R or Eibach springs, so have no basis for comparison in ride feel, but I suppose it's possible that you'd lose some of the CP handling if you changed out the springs?

[dhirm5]

I'd prefer a slightly bigger drop - especially in front. Eibachs lower by 0.9" in front and 0.7" in back; CP drop is .4" all around. That half inch in front would really tighten up the stance, imho.

Based on this data, I won't be doing it. Eibachs are softer at the highest progressive rating than CP's springs. CP is 20% stiffer than standard, and the Eibach's highest rate is ~12% stiffer than standard in back and ~9% in front.

[RPiM5]

Originally Posted by dhirm5

I'd prefer a slightly bigger drop - especially in front. Eibachs lower by 0.9" in front and 0.7" in back; CP drop is .4" all around. That half inch in front would really tighten up the stance, imho.

Based on this data, I won't be doing it. Eibachs are softer at the highest progressive rating than CP's springs. CP is 20% stiffer than standard, and the Eibach's highest rate is ~12% stiffer than standard in back and ~9% in front.

Interesting and great info Alok.

So it seems the Eibachs will provide a softer than Comp Pack but a stiffer than stock ride quality, but still present a more aggressive drop in ride height than Comp Pack springs. I think the Eibachs might be a better compromise for those looking for a more aggressive stance and a more comfortable ride quality than Comp a Pack. Which is what I would be looking for. On my last M5 I made the car too stiff for the street but it handled fantastic on the track. I vowed to never go that aggressive again cause it just made the M5 un-enjoyable.