Nitrous Oxide Distribution Block
Fragola Performance Systems 900620-BL Nitrous Showerhead Distribution Block 3/8 FPT Inlet 1/4 FPT Outlets (4) Black
Nitrous Express 15940-MT Stand Alone Battery Operated Bottle Heater 10-15lb 4AN Makita Style
Nitrous Express 15019R 4-Port Showerhead Nitrous Distribution Block 6AN Inlet Red
Nitrous Express 15019B 4-Port Showerhead Nitrous Distribution Block 6AN Inlet Blue
What Is a Nitrous Oxide Distribution Block?
In a direct port nitrous injection setup, delivering an equal charge of nitrous — and fuel in wet applications — to every cylinder is critical to making reliable power. That's precisely the job of a nitrous oxide distribution block. Acting as the central hub of a direct port system, this precisely machined component accepts a single high-pressure nitrous (or fuel) inlet and splits the flow evenly across multiple outlets, one for each cylinder in the engine.
Nitrous oxide distribution blocks are only required in direct port systems, which use individual injector nozzles plumbed directly into each intake port rather than a single plate or fogger nozzle upstream of the manifold. This design gives tuners the finest level of control over nitrous delivery, allowing for cylinder-by-cylinder tuning and the highest achievable power levels from a nitrous system.
Why Even Distribution Matters
Consistency is everything in a nitrous system. An uneven split — even a slight one — means some cylinders receive more oxygen-rich nitrous charge than others. The result can range from a lean misfire in one cylinder to catastrophic detonation. A quality distribution block eliminates this risk by ensuring each outlet flows the same volume at the same pressure, keeping air-fuel ratios balanced across the entire engine under boost.
Direct port nitrous systems operate under significant pressure, and the lines that carry nitrous from the bottle to the solenoid can run at around 1,000 psi at peak. Distribution blocks must be machined to tight tolerances and built from materials capable of handling this sustained pressure without leakage or deformation. Most quality blocks are CNC-machined from billet aluminum for strength, light weight, and corrosion resistance.
Key Considerations When Shopping
- Cylinder count compatibility: Distribution blocks are most commonly available in 4-outlet, 6-outlet, and 8-outlet configurations to match 4-, 6-, and 8-cylinder engines.
- Port sizing (NPT): Blocks typically use 1/8" NPT inlet and outlet threads, though some configurations use 1/16" NPT outlets for lower-flow applications. Always verify fitting compatibility before ordering.
- Wet vs. dry systems: In a wet direct port setup, you'll need separate distribution blocks for nitrous and for fuel — one of each, matched to your solenoid and line configuration.
- Material and finish: Billet aluminum blocks offer the best combination of strength and weight. Anodized finishes add corrosion resistance and a clean, race-ready appearance.
- Flow balance: Look for precision-machined designs engineered specifically for balanced flow rather than generic plumbing fittings, which can introduce unequal flow paths.
Top Brands in Nitrous Oxide Distribution Blocks
NOS (Nitrous Oxide Systems) is the undisputed pioneer of automotive nitrous injection. Founded in the late 1970s and now a brand under Holley Performance Products, NOS has powered more racers than any other nitrous brand and was present at virtually every major nitrous-powered performance milestone in motorsport history. Their distribution blocks are precision machined from high-quality billet aluminum to deliver balanced nitrous and fuel flow to each intake port, and are available in multiple configurations to support a variety of direct port builds.