CP Pistons SC7541-4 Forged Piston Kit 83.5mm for Mazda Miata BP 1.8L

Vehicle Fitment

• Mazda Miata / MX-5 - BP series 1.8L (BP, BP-VE, BP-ZE, BP-ZET, BPT engines)

Fitment Notes

• 83.5mm bore (+0.5mm over stock) - confirm block has been bored to this size, or budget for machining
• Suitable for naturally aspirated, turbo, supercharged, or nitrous applications

Features

• Forged dome-top design with four valve reliefs for higher compression and boost tolerance
• Dedicated forgings, not generic blanks, for each application
• Balanced to within ±1 gram set-to-set for smoother operation
• Accumulator grooves and dual forced pin oilers for improved ring seal and lubrication
• Pick lock grooves for secure pin retention
• Fully CNC-machined for tight tolerances
• Wrist pins and pin fitting included at no extra cost
• USA manufactured at CP-Carrillo's Irvine, California facility

Specifications

• Bore: 3.287" (83.5mm, +0.5mm over stock)
• Stroke: 85.0mm
• Rod length: 133.0mm
• Compression height: 30.68mm
• Pin diameter: 20mm
• Compression ratio: 9.0:1

Included Components

• 4x Forged pistons
• 4x Wrist pins
• 1x Set of piston rings
• Pin locks

Product Description

The CP Pistons SC7541-4 is a forged piston and ring kit built for the Mazda Miata's BP 1.8L engine, sized at 83.5mm (+0.5mm over stock) to suit a bored block. Each piston is a dedicated forging rather than a generic casting, engineered through CP's computer modeling and 5-axis machining process for consistent, precise geometry across the set.

With a 9.0:1 compression ratio, dome-top design, and four valve reliefs, this kit is built to handle naturally aspirated, turbocharged, supercharged, or nitrous-assisted builds. It's a solid choice for Miata owners rebuilding or upgrading their bottom end for increased power and reliability, with wrist pins and pin fitting included as part of the kit.