Supertech Mazda Miata 1.8L 84mm 30.5mm CH -4cc Dish 8.7:1 CR Piston - Set of 4 (Excl Rings)

If you're rebuilding the engine in your Mazda Miata and looking to improve its performance or durability, a set of forged pistons like these from Supertech is a solid choice. These pistons are designed for the 1.8L engine and feature an 84mm bore, which is a common size for engine builds. They come with a -4cc dish, contributing to an 8.7:1 compression ratio, a good balance for many performance applications where you might want a bit more power without sacrificing too much drivability or requiring extremely high octane fuel.

Forged pistons are made from a solid block of aluminum that's heated and hammered into shape, making them significantly stronger and more resistant to detonation and high temperatures compared to cast pistons. This strength is crucial for engines that see harder use or have been modified. The 30.5mm compression height is a specific measurement that ensures these pistons will work correctly with your connecting rods and crankshaft to achieve the correct piston-to-valve clearance and deck height. Remember that these pistons do not include piston rings, so you'll need to purchase those separately to complete the assembly.

When installing these pistons, it's important to follow the manufacturer's recommended clearances and procedures. Because they are forged, they can expand slightly more than cast pistons under heat, so precise machining and proper installation are key to a long-lasting engine. This set is not CARB approved and cannot be shipped to California.