Quote:
Originally Posted by Nezil
So I'm no suspension expert, but I'm starting to see a trend...
When the OG M2 first came out, one of the first suspension upgrades available was the Dinan kit which re-uses the stock struts just like MSS, and replaces the springs with a stiffer spring rate. Dinan replaces both the front and rear bump stops with shorter BMW OEM parts from other vehicles
MSS doesn't tell us their spring rates, but we do know that they replace the fronts bump-stops with their own, and keeps the stock rears.
Those that drove the Dinan kit commented on improved comfort, despite the fact that the springs were actually stiffer. MSS now claims that lowering is possible with increased comfort and grip, and that's what OzWoz is finding. The comfort is not in the low suspension travel region, but more for bigger bumps where the bump stop would be engaged in the stock setup.
The trend I think we might be seeing is that it's possible to improve comfort by using more of the spring rather than the bump stop. If a system can be designed to allow more travel with the spring before the bump stop comes in to play, or a bump stop with a more progressive travel, comfort will improve.
The only thing I'm struggling with is the added grip. Softer suspension would achieve that, and that might be possible if the rear bump stop were changed to allow for more travel than stock before engagement, even with a higher spring rate, but without changing the bump stop, lowering reduces travel, a stiffer spring could slow bump stop engagement but in order to achieve that, the result would need to be stiffer than stock and therefore reduce grip.
One possibility is that MSS' trick multi-spring setup is creating a progressive system where a soft initial spring provides more grip with low excursion, and then the second spring is really very stiff preventing bump-stop engagement. If the weight transfer on acceleration of the M2 is relatively small, this small amount of soft spring rate travel might be enough to improve grip?!?
I'd love to see a Go-Pro in the rear wheel well during a drive!
|
You say as if the suspension rides on the bump stop all the time...
The top hat does not hit the bump stop unless the travel is most extreme (like hitting a huge bump or pot hole).