Wow... been away for a bit and missed quite a bit.
Let me bring in a little more of what MeisterR do and why we do it.
MeisterR Springs rate:
We don't just pick springs rate out of thin air (mind you alot of suspension supplier do).
We have a UK workshop with a vehicle dynamic engineer worth over 20 years of experience providing suspension from OEM to Pike Peak race car application.
Some people think we have a very soft springs rate, but actually in the "grand scheme" of things, it isn't that soft.
A lot of suspension go "Because RaceCar" and just pop in stiff springs, and there are a few reason for it such as lacking compression force, or just want to give a stiff ride as that is what they think their customer expect.
This is another reason why many "feel" coilovers will provide a harsh ride, because they have got coilovers that just weren't design for street use.
The MeisterR ZetaCRD coilovers for the Fiesta is actually on the top end of what we classify as a "Fast Road" suspension.
OEM normally go much softer, so our springs rate may seems soft if you compare it to other coilovers; but it isn't soft if you work out the numbers and compare it to a "street suspension".
What that mean is the ZetaCRD will allow you adjust the damping soft for good compliant ride quality, you won't drive 2 hours on the freeway and get fed up with the harsh ride.
Of course, everyone preference and tolerance are different, but that is why we engineer our suspension using vehicle dynamic principle as it provide us a level field to base our suspension specification.
MeisterR Damper
The ZetaCRD coilovers are made oversea, but they are made to MeisterR specification with high tolerance control.
We also spot check our suspension at our UK workshop, and that mean we know if any "raw" parts are not right because we see them.
This is one HUGE difference that separate MeisterR to many other brands, because we are our own workshop, research and development, as well as supplier all under one roof.
We have access to technical expertise that most supplier do not have, and that include the factory that build our suspension.
Everything we do are unique to MeisterR, and all are guarantee under a non-discolusre agreement.
Basically, even the factory that makes MeisterR suspension couldn't use our specification on their own product, because that will mean they breach our contract.
The ZetaCRD damper valving is our unique design, and they are Compression and Rebound adjustment combined for GOOD REASON.
Having combined adjustment is the ONLY way to make a good fast road & track suspension, and if anyone want to say rebound only is best I am happy to spend hours talking about vehicle dynamic with them.
But I will have a quick explanation of why we want compression and rebound combined, as that is the entire basis of the ZetaCRD damper.
The CRD stand for "Close Ratio Damping"
Generally speaking, you want to have a good damper ratio between compression to rebound.
For fast road car, you want it to be around 1:3, down to 1:2 for track use car.
We will go down to 1.5:1, that is normally as far as we want to go; and you will find some race damper such as Ohlins that will go down to 1:1. (which even we think is a bit "out there").
So what is all this ratio?
First, one have to understand what compression and rebound control:
Compression: Control how fast load are applied to the tires. Basically it control how hard do you work your tires, also determine your steering response and ride comfort.
Rebound: Control motion of the car. Basically it control how fast body roll happen, and how "stable" car feel.
For a particular level of rebound force, you want to have a good ratio of compression force; that is what separate a good damper to a bad one.
Say you have the correct rebound force for a car, but very little compression force; what that will do is the car feel planted, but you are not working you tires.
What that mean is you are not making the grip that you should, and therefore you are no achieving performance that you should be getting from the tires.
BUT... it will feel comfortable because you aren't putting force against the tires.
This is where the damping adjustment comes in:
For rebound force, it works with the paired springs rate. A particular springs rate can support a certain maximum rebound force, we call that critical rebound.
For track car, you want to be at 100% critical rebound; fast road will be anything between 70% to 50%.
Rebound adjustment only (assuming it is critical damping is 100kgf, and 1:3 ratio)
If it was design to hit that ratio at maximum adjustment, you will have the following figure:
Compression : Rebound - Ratio
33 : 100 - 1 : 3
33 : 70 - 1 : 2.1
33 : 50 - 1: 1.51
If it was design to hit that ratio at minimum adjustment, you will have the following figure:
Compression : Rebound - Ratio
16.5 : 100 - 1 : 6
16.5 : 70 - 1 : 4.2
16.5 : 50 - 1: 3.1
No matter which way you do this, the long as you have a large adjustment available in the rebound force, you damping ratio will go way out of spec on one end of the spectrum.
Compression / rebound combined adjustment solve this problem because the compression move with the rebound and thus keep the ratio closer to the ideal point.
Okay, this might be a lot of reading.
I just want to bring some info up front and to say that we don't do things because it is a gimmick.
Everything MeisterR do are design with a purposes in mind, backed up by vehicle dynamic principle.
We don't put something on a car and hope it works, we build something for a car because we know it is going to work.
Jerrick