45 Degree Transition Hose 3in I.D. to 4in

The 45 Degree Transition Hose 3in I.D. to 4in is a precision engineered intake and exhaust ducting component designed for custom engine builds, turbocharger installations, and high-flow air management systems. This angled transition fitting solves a critical problem mechanics and enthusiasts face: connecting mismatched diameter hoses or piping when space constraints or engine bay layouts prevent straight runs. Whether you're fabricating a custom intercooler setup, rerouting boost lines on a supercharged engine, or integrating a larger intake manifold into an existing system, this 45-degree transition eliminates the need for expensive custom bends or restrictive adapters.

Built to handle boost pressures and thermal cycling common in performance applications, this transition hose features a 3-inch inner diameter inlet that steps up to a 4-inch outlet, allowing seamless integration between smaller boost tubes and larger diameter piping without abrupt pressure losses or turbulence. The 45-degree angle design minimizes flow disruption compared to 90-degree fittings, maintaining velocity and reducing heat generation in sensitive systems like turbo plumbing or intercooler circuits. Constructed from durable reinforced materials capable of withstanding vacuum and positive pressure conditions, the hose resists kinking and maintains dimensional stability under the vibration and temperature swings typical of engine compartments, with a compact footprint of approximately 13 inches that fits tight modification spaces.

This transition hose benefits fabricators, turbo installers, and weekend builders working on custom cooling systems, forced induction upgrades, or engine swaps where OEM ducting doesn't accommodate larger aftermarket components. It's ideal for intercooler piping, custom air intake paths, or vacuum line consolidation on modified engines. Standard hose clamps compatible with 3-inch and 4-inch diameters secure both ends, making installation straightforward on any project car, truck, or performance engine platform where smooth diameter transitions are critical to maintaining system efficiency and reliability.