FM springs are well known for providing a good balance of street ability and track performance. Their combination of ride height - giving the suspension room to work - and spring rate means your Miata will ride and handle better than you would expect from a set of performance springs.
There's more going on than you think, though. See that section with the tighter coils? Those are designed to act as a secondary spring, keeping the spring from going loose under full droop. While these rates might sound high compared to some other springs on the market, they are stiff enough to keep your car off the bump stops. Softer springs will often give a worse ride because they allow you to blow through your suspension travel and end up on the stops. We've specified a powder coat with a high zinc content for extra corrosion resistance, too.
How much will they lower your car? We can't tell you, because Mazda changed the ride height of Miatas over the years. However, if you measure from the centre of the wheel to the fender lip, you can compare your car to the final result. It's not slammed but once you drive the car you'll appreciate how well it works.
Specifications:
Front springs: 300 lb/in
Rear springs: 196 lb/in
Front ride height: 13.5"
Rear ride height: 13"
Ride height can vary based on your shocks, but the numbers above are what they are with Koni Sports and should be close to other stock-format shocks.
Set of four. Not recommended with stock shocks - the higher spring rates are too much for stock shocks to handle. These will only work with stock-format shocks, such as our Koni Sports, they won't work with coilovers like Foxes.
Compatible with both soft top and power hardtop Miatas. The spring rates of our springs are high enough that the extra 80 lbs doesn't make a significant difference. Please note that the car needs to be on its wheels (and rolled back and forth a few times) when the various suspension bolts are tightened up, or this will lead to a high ride height and rapid bushing failure. We've also heard of people installing the removable perch on NC Bilstein Sport shocks upside down, leading to a ride height approximately 2" above normal. This is not a problem with the Koni shocks we use in our packages.