SPDZ1 B-Series Big-Tube 4-2-1 Tri-Y Header — B16 / B18 / B20 Swap | SZY-065

Give your B-series swap a compact, one-piece exhaust upgrade. The SPDZ1 SZY-065 Big-Tube 4-2-1 Tri-Y Header combines stepped runners, a 2.5-inch collector and 304 stainless steel in a welded assembly for naturally aspirated B-series builds.

Designed for B-Series Swap Builds

The four runners merge into two secondary pipes before meeting at a single collector. This Tri-Y layout is aimed at low-to-mid-range response, while the short-tube routing helps manage engine-bay space and ground clearance. Actual power and clearance depend on your engine, mounts, chassis and exhaust setup.

Key Features

• 4-2-1 Tri-Y layout with stepped tubing
• One-piece welded construction without a slip-fit joint between header sections
• 18-gauge 304 stainless steel with a polished finish
• 2.5-inch collector with a flanged outlet
• CNC-machined cylinder-head flange, approximately 0.38-inch thick
• Compact routing for B-series swap applications

Application & Fitment

Intended for Honda/Acura B-series swap builds using B16, B18 or B20 engine configurations, including built combinations within the reference application range of 1.6–2.2L. This is a swap-specific header: engine family alone does not establish chassis fitment.

Confirm your cylinder-head flange, engine-mount position, oil-pan and subframe clearance, collector location and exhaust connection before ordering. This listing does not establish universal bolt-on fitment for every Civic, Integra, CRX or Del Sol, and does not cover H22/H2B applications.

What’s Included

• One SPDZ1 SZY-065 one-piece 4-2-1 header assembly
• Cylinder-head gasket and collector sealing gasket shown in the product photos

Sold as one header set. Product photos show the supplied header and gaskets.

Installation Notes

Professional installation is recommended. Match the collector flange to your existing exhaust; fabrication or an adapter may be required. Confirm oxygen-sensor placement and wiring needs for your build. No fixed horsepower gain or factory-exhaust connection is guaranteed.