The ND is already a phenomenal sports car, but there are ways to improve it - a high-quality lightweight flywheel is a good one. We have two versions (that are NOT interchangeable) - one for the ND1 (2016-2018) and one for the ND2 (2019+). Both are drop-ins and work great with both our clutch and the ND1 stock clutch (NOT the ND2 clutch*). The weight loss (about five pounds) is great, but since the weight loss is in a rotating piece of the drivetrain specifically designed for inertia, the benefits are even better. This will basically make your car into more of a sports car by making the engine "revvier". Sounds like marketing, but it's true - easier rev-matching, better engine braking, and better acceleration (slightly, and only in lower gears) make your car into an even better sports car. As with all of our flywheels, this is a single-piece chro-moly unit so it's long-term reliable and can be machined if you need to replace the clutch. While our ND1 (2016-2018) flywheel is a great unit, with all of the improvements noted above, our ND2 (2019+) flywheel is the really special one. Unlike every other Miata, the ND2 Miatas have a dual-mass flywheel. This is good because it can help smooth out the driving experience, including decreasing shock loads on the transmission. This is bad because it makes for a heavy flywheel, and because it's possible for them to fail. However, the big reason you want to get rid of it is that it puts a big damper in the driveline, somewhat disconnecting the engine from the wheels. Miatas are all about being connected, right? Our lightweight ND2 flywheel eliminates the dual-mass mechanism while also dropping about 4 lbs. Getting rid of the dual-mass mechanism eliminates the "rubber band" in your driveline, which is huge. Those two things together mean much sharper responses and dramatically more of a sports car experience. We always like lightweight flywheels for our driving styles, but we really like the lightweight flywheel for the ND2. The stock ND1 flywheel is 15.4 lbs while ours is 10.2 lbs, the ND2 stock flywheel is 19.0 lbs while ours is 15.0 lbs. *Note that while both the ND1 and ND2 stock clutch will physically fit with our flywheels, we don't recommend using the stock ND2 clutch with our ND2 flywheel. While our clutch and the stock ND1 clutch have sprung center sections to absorb some of the shock load, the ND2 clutch doesn't, as it relies on the dual mass flywheel to do that. No problem, but that means that if you combine our ND2 flywheel and the stock ND2 clutch, you have no means to absorb that shock load. This will make the car much less smooth to drive and makes transmission damage more likely. If you'd like the lightweight flywheel and a stock clutch for your ND2, use our ND2 flywheel and a stock ND1 clutch. As with all lightweight flywheels, there's the possibility of increased noise in closed-throttle, in-gear deceleration. This typically sounds like a minor rattling - a small thing that might not happen, but something to be aware of. This also isn't a great choice for drag racers, as there's less inertia so it can be a tick harder to launch. Bear in mind that since dual-mass flywheels can damp shock loads from the engine to the transmission, your ND2 transmission's warranty might be voided by installing this flywheel (not an issue for the ND1). As long as you don't drive abusively (slamming shifts, dropping the clutch, etc.) you shouldn't have any issues.
