So against my better judgement, I wound up getting non-FM coilovers, and the damping seems to have gone away after not very many miles (I know, I know, how dumb can I be? Read on...), so I'm thinking I should go with a tried and true set up, and where I can play with damping a little bit.
But, like the title of this thread says, here's the dumb idea:
FM springs I think put a NB at 12.5/13 ride height, but I really like the look of the car now at, probably 11-3/4 and 12-3/16 (yes, I've adjusted the ride height in 3/16" increments...).
I had seen somewhere, I thought even authored by Keith, that one of the dead coils could be cut from the springs to get to 12/12.5 - but I don't know how old that information was, nor whether or not Keith (if he wrote it) would still advise it.
One might ask, why not go with the VMaxx adjustable coils? Good question - and so I'll add that to the mix.
I thought the Koni's might be a longer lasting set up.
Yes, no, maybe?
You could maybe call them at FM and ask directly.
I don't know that the Koni's would be worth it over the V-Maxx as they both are quality products and are rebuildable in the event of their wear and the V-Maxx would allow you to have your cake and eat it too.
I never advised it, just acknowledged that it was possible 
We got enough questions asking if the springs could be cut that we described how to do it correctly, but nobody at FM will say it's a good idea.
Problem is, when you lower a car and you don't do anything to the spring rate or change any geometry, you lose a bunch of travel. This leads to a poor ride and bad handling as you ricochet off the bumpstops.
The V-Maxx cannot be rebuilt, by the way.
In reply to Keith Tanner:
Only to get that extra half inch, would that affect things that much? Would the Koni's wear out appreciably faster?
I'm a slave to fashion, yet still like to drive it. It wouldn't kill me (though close) that the car would be a weensie bit higher than it is now, but any higher and I'll be forever sad.
An orphan between stance and performance, I guess.
You could get Koni yellows and GC sleeves, if you're so inclined.
I have the VMaxx, and like them, on an NA (to add a data point)
The Konis would not wear out faster.
The extra half inch would mean they wouldn't work as well as they did before. Would it make the car undriveable? Probably not, especially given what you're rolling on now. But you would be sacrificing performance for looks, and you would bottom out more often.
Same if you went for GC sleeves.
These are on an NA, right? Then you can accomplish the same thing by using the lower perch positions on the Koni shock body. That'll let you experiment. If it's an NB, have a machinist put an extra groove in the body and you can do the same thing.
Keith, NB.
You had previously mentioned that NA units on a NB would reduce ride height, but I don't recall why without re-reading that thread (it was a chance to pick up some Tein Springs on Bilsteins for $100... "missed them by that much").
Could I get away with NA units at the highest perch setting?
Practically speaking, neighborhood speed bump constraints and livability therewith mean the car shouldn't/can't be below the 12/12.5 range anyway.
The NA units won't work with with NB springs nor will they happily mate to NB upper mounts.
Konis don't take well to being bottomed out. In fact one or two goid hits and you will destroy tge valving and at tgat po III NT it I not even wort rebuilding them. Cost wise new were a better deal.
So be very careful about lowering a car with konis. You either have to use the koni bump stops that go on the shocks/struts or make sure your suspension is set up so the suspension stops hit before the koni bottoms on the tube.
Cutting out "just one coil" could result in you trashing tge konis if you don't take in to account the change in the strut geometry.
Complete NA package (springs too), or will it not bolt up (as I thought it would)?
I can see you shaking your head in bemused disbelief from here... 
I'd say I can scarcely believe I'm asking such a stupid question, but that would be a lie - I really should just spend the $1,500 for "good" CO's but I'm cheap.
Especially as I'll be set at 12/12.5 no matter what route I take.
FM Springs with Konis were good to me for performance. I wouldn't change the springs just for looks. The stance is pretty low IIRC anyway with the FM springs once they settle in.
dean1484 wrote:
Cutting out "just one coil" could result in you trashing tge konis if you don't take in to account the change in the strut geometry.
Not an issue on the Miata application, FYI. The shock ramming into the bumpstop is how the suspension limits are reached, intentionally. Cutting the springs does not change this geometry.
OldGray320i wrote:
Complete NA package (springs too), or will it not bolt up (as I thought it would)?
Will not. The NA upper mounts will not fit through the holes in the NB chassis, IIRC. The smaller NB mounts will fit through the bigger holes in the NA chassis which is why you can go the other way.
Here's how the FM springs sit with no modifications.
When I ran the FM 2.5 suspension (like above) after 6 months or so I cut one of the "dead" coils from the rears. No problems resulted and it dropped about 1/2".
