Eagle CRS5233M3D Forged H-Beam Connecting Rods Set for 1990-2005 Mazda Miata BP

Vehicle Fitment

• 1990-1997 Mazda Miata (Base, SE, LE, M Edition) 1.6L B6 NA I4
• 1999-2005 Mazda Miata (Base, SE, LS, 10th-Anniversary, Mazdaspeed) 1.8L BP NA I4

Fitment Notes

• Does **not** fit turbocharged or forced induction setups unless supporting modifications are made (fuel, cooling, balancing, etc.).
• Uses floating wrist pin design; ensure pistons support floating pins or conversion.
• Drivetrain must be stock or upgraded to handle increased rod strength; engine block in standard BP/B6 configuration.
• Fitment confirmed through 2024; 2025 Miata variants with BP/B6 engines are rare and thus 2025 is unconfirmed.

Features

• Forged SAE-4340 steel H-beam design for improved strength and fatigue resistance. 
• Shot-peened, magnafluxed, sonic-tested, and X-rayed to ensure structural integrity.
• Weight matched set (≈ 535 g per rod) with very tight tolerance to ensure balance.
• Bushed for full-floating piston pin; floating wrist pin compatible.
• Precision cap alignment sleeves ensure proper big-end cap seating. 
• Uses ARP 2000 3/8-inch rod bolts for high strength and secure fastener retention. 
• Center-to-center length of 5.233" (≈ 132.9 mm), optimized for BP/B6 engine geometry.
• Big end width & pin end width ≈ 0.858"; housing bore ≈ 1.89"; pin diameter ≈ 0.787"; all confirmed specs. 

Specifications

• Material: Forged SAE-4340 steel. 
• Center-to-center rod length: 5.233" (≈ 132.9 mm).
• Big end bore (housing bore): ≈ 1.890".
• Rod journal (big end journal diameter): ≈ 1.770". 
• Pin (wrist pin) diameter: ≈ 0.787". 
• Big end width and pin end width: ≈ 0.858" each. 
• Rod bolts: 3/8-inch ARP 2000. 
• Typical rod weight: ≈ 535 grams. 

Included Components

• 4x forging 4340 steel H-beam connecting rods (weight-matched set)
• 4x ARP 2000 3/8-inch rod bolts
• Rod cap alignment sleeves
• Instructions + rod bolt lubrication guide

Product Description

The Eagle CRS5233M3D is a high-performance connecting rod set engineered for Mazda BP/B6 series engines - specifically the original Mazda Miata (MX-5) models from 1990 through 2005 using the 1.6L B6 or 1.8L BP naturally aspirated four-cylinder engines. Built from forged 4340 steel, each rod is subjected to rigorous quality processes including shot-peening, magnaflux, sonic testing, and X-ray inspection to ensure superior strength, reduced risk of failure, and excellent durability in high-RPM or performance applications.

These rods are ideal for engine rebuilds, naturally aspirated performance upgrades, or mild boost setups that stay within safe limits. Installation requires proper handling: torque ARP 2000 rod bolts to 43 ft-lb using a moly lubricant, verify compatibility with floating wrist pins, piston pin design, and engine block integrity. Fitment is confirmed through 2024 across the listed Miata models. 2025 Miata models with BP/B6 engines are not verified - 2025 unconfirmed.