Mikado B20A Conversion Rods – 21mm Pin | 4340 Forged Steel | 600HP+

The Honda B20A platform has been held back by its factory geometry for decades. Mikado Engineering changes that. These custom-spec conversion rods adapt your B20A, B20A5, B20A6, or B20A7 to a 21mm wrist pin, unlocking the full range of off-the-shelf Honda B16/B18 forged pistons — no expensive custom work required.

Machined from Forged 4340 Aircraft Quality Steel (40CrNiMoA), shot-peened and Magnafluxed, and rated for 600HP+. Shipped with high-tensile 3/8" racing bolts meeting or exceeding ARP 2000 spec.

Engineering Specifications

• Platform Fitment: Honda B20A / B20A5 / B20A6 / B20A7
• Material: Forged 4340 Aircraft Quality Steel (40CrNiMoA)
• Design: H-Beam
• Processing: CNC Machined, Shot-Peened, Magnafluxed
• Power Rating: 600HP+
• Center to Center: 141.5mm
• Big End Diameter: 51.01mm
• Small End Diameter: 21mm (Bushed – QAL10-3-1.5 Bronze)
• Pin Type: Floating (piston locks required)

Fastener Specs

• Bolt: 3/8" High-Tensile Forged Steel
• Tensile Strength: 228,000 PSI
• Torque Spec: 75 Nm

Pre-Order Notice: Final QA testing is underway on our development vehicles. Orders now secure allocation from the first production batch — estimated shipping within 2 months.