Supertech Mazda Miata 1.8L 84mm Bore 10.5cc Dome 11:1 CR Pistons - Set of 4 (Excl Rings)

If you're rebuilding the engine in your Mazda Miata and looking to increase compression, these Supertech pistons are a solid option. This set is specifically made for the 1.8L engine and features an 84mm bore, which is the standard size for most 1.8L Miata engines. The 10.5cc dome volume combined with the piston shape helps achieve an 11:1 compression ratio, a notable bump from stock that can improve power and throttle response when paired with appropriate tuning.

These pistons are forged from high-strength aluminum alloy, a common practice for performance engine components because it offers a good balance of durability and weight. Forged pistons are generally more resistant to detonation and fatigue compared to cast pistons, making them a good choice for engines that see spirited driving or track use. The 84mm bore means these are a direct replacement for stock-sized pistons, simplifying the machining process for your engine builder. It's important to note that this set includes the pistons only; you'll need to source piston rings separately, as they are not included.

When installing these pistons, ensure your engine builder is aware of the specific dome volume and compression ratio they achieve. Proper balancing of the rotating assembly, including these new pistons, is crucial for engine longevity. Remember that increasing compression may require higher octane fuel and ECU tuning to take full advantage of the improved performance and avoid potential issues like knocking.