Vehicle Fitment

• 2015–2024 Ford Mustang GT (S550/S650, 5.0L Coyote V8, Coupe & Convertible, All Trims)
• 2019–2023 Ford Mustang Bullitt (S550, 5.0L Coyote V8, Coupe)

Fitment Notes

• REQUIRES BBK long tube headers for installation — this short mid-pipe is a dedicated adapter designed to connect BBK long tube headers to the factory cat-back or aftermarket cat-back exhaust system. It is NOT designed for use with factory shorty manifolds or aftermarket shorty headers.
• Confirmed compatible with BBK long tube headers: Part #1633 / 16330 (1-3/4" Titanium Ceramic / Polished Silver Ceramic) and Part #1856 / 18560 (1-7/8" Titanium Ceramic / Polished Silver Ceramic).
• Features a merged 3" to 2.5" step-down at the cat-back connection — allows use with the factory OEM cat-back, a BBK 2.5" cat-back, or any other brand of 2.5" aftermarket cat-back exhaust system.
• Factory O2 sensor bung locations are maintained — all sensors plug in directly at the stock positions with no relocation or extensions required.
• A handheld tuner is recommended (but not always required) to disable rear oxygen sensors and prevent catalyst under-temperature check engine light codes. Due to the sensitive emissions monitoring on 2015–2024 Coyote Mustangs, even high-flow catalytic converters can occasionally trigger a catalyst undertemp code.
• NOT CARB Approved — these catalytic converters do not carry a CARB EO number and are not legal for sale, installation, or use in California or any state that has adopted California emissions standards. Federal EPA N/CE compliant for 49-state use.
• Sold as a pair (left and right mid-pipe sections).

Features

• Completes the long tube header installation on 2015–2024 S550/S650 Mustang GT — bridges the 3" long tube header collector outlet to the factory 2.5" cat-back exhaust system in a single bolt-on kit, eliminating the need for custom fabrication.
• 3" CNC mandrel-bent aluminized steel tubing throughout the main body — maintains a consistent round cross-section and maximizes internal flow area, working in concert with the long tube headers to deliver maximum exhaust velocity and scavenging benefit across the full RPM range.
• Merged 3" to 2.5" step-down reducer at the rear connection transitions smoothly from the 3" mid-pipe diameter to the 2.5" factory or aftermarket cat-back connection with no turbulence-inducing abrupt transitions.
• High-flow catalytic converters pre-installed — improve exhaust flow over the restrictive factory cats while retaining emissions equipment in the system, meeting Federal EPA requirements for new aftermarket converters (N/CE classification).
• Factory-style O2 sensor bung placement — all oxygen sensors install at the original factory positions for a seamless, plug-and-play integration with the Mustang's PCM and emissions monitoring systems.
• Pre-welded exhaust hangers at factory locations — direct, secure mounting to the chassis without additional hardware or modification.
• Compatible with the factory OEM resonator/cat-back section or any aftermarket 2.5" cat-back exhaust brand — providing full flexibility in building out the complete exhaust system beyond the mid-pipe.
• Significant horsepower and torque gains when used in combination with BBK long tube headers — combined system gains of 20–30+ rear wheel horsepower have been documented depending on the header choice and additional modifications.
• Made in the USA — designed and built domestically by BBK at their multi-facility manufacturing campus since 1988.

Specifications

• Part Number: 1816
• Product: CNC Series Short High-Flow Mid-Pipe Kit with Catalytic Converters
• Application: 2015–2024 Ford Mustang GT / 2019–2023 Bullitt — 5.0L Coyote V8 (S550/S650)
• Required Upstream Component: BBK Long Tube Headers #1633, #16330, #1856, or #18560
• Pipe Diameter (main): 3.000 inches (CNC mandrel-bent)
• Rear Connection: 3" to 2.5" merged step-down (compatible with 2.5" OEM or aftermarket cat-back)
• Tubing Material: Aluminized Steel
• Tubing Fabrication: CNC Mandrel-Bent
• Catalytic Converters: Yes — 2x High-Flow Catalytic Converters (pre-installed, Federal EPA N/CE compliant)
• O2 Sensor Bungs: Yes — Factory Location (direct plug-in)
• Exhaust Hangers: Pre-welded (factory location)
• Clamps Included: Yes
• Hardware Included: Yes
• Quantity: Sold as a pair (left and right)
• Emissions: 49-State Legal (Federal EPA N/CE) — NOT CARB Approved (not legal in California)
• Country of Origin: USA
• Warranty: 1-year manufacturer's warranty from date of purchase

Included Components

• 2x BBK 3" High-Flow Short Mid-Pipe Sections (Left and Right, Aluminized Steel, CNC Mandrel-Bent)
• 2x High-Flow Catalytic Converters (pre-installed, one per mid-pipe section)
• 1x Set of Clamps and Installation Hardware

Product Description

The BBK 1816 3-Inch High-Flow Catted Short Mid-Pipe Kit is the required connecting piece between BBK's long tube headers and the factory or aftermarket cat-back exhaust system on the 2015–2024 Ford Mustang GT and 2019–2023 Bullitt. When BBK long tube headers (part numbers 1633/16330 or 1856/18560) are installed on the S550 or S650 Coyote Mustang, the 3" collector outlet diameter does not match the factory 2.5" cat-back inlet — the 1816 mid-pipe bridges this gap with CNC mandrel-bent 3" aluminized steel tubing that transitions smoothly to a merged 3"-to-2.5" step-down at the rear, allowing the complete system to bolt to the factory resonator or any 2.5" aftermarket cat-back without custom fabrication. Combined with the long tube headers, the 1816 mid-pipe completes a free-flowing exhaust path from the cylinder heads to the tailpipe that has produced documented gains of 20–30+ rear wheel horsepower depending on header selection and additional modifications.

Two high-flow catalytic converters are pre-installed at the factory, meeting Federal EPA new aftermarket converter (N/CE) requirements for 49-state street use. Factory O2 sensor bung locations are maintained throughout, allowing all oxygen sensors to plug in directly at their original positions for seamless integration with the Mustang's PCM. Pre-welded exhaust hangers align with the factory chassis mounting points for a secure, rattle-free installation. Clamps and hardware are included in the kit for a complete bolt-on installation alongside the BBK long tube headers.

Due to the sensitive emissions monitoring architecture on 2015–2024 Coyote Mustangs, a handheld tuner is recommended (though not always required) to disable the rear oxygen sensors and prevent catalyst under-temperature check engine light codes that can occur even with high-flow catalytic converters. This product is not CARB certified and cannot be sold, installed, or used in California or any state following California emissions standards. Made in the USA and backed by BBK's 1-year manufacturer's warranty, the 1816 mid-pipe is an essential companion to any BBK long tube header installation on the S550 or S650 Mustang GT platform.