Inverted Flare to AN Adapter

A 45 degree flare will thread onto a 37 degree seat and betray you at full oil pressure.

Turbochargers with inverted flare oil feeds and plenty of OEM hard lines use the SAE inverted flare standard. The Finish Line Factory Inverted Flare to AN Adapter carries a inverted (SAE 45 degree) flare connection on one side and a male 37 degree AN flare on the other, in AN sizes 4AN, 6AN, 8AN with port sizes 5/8 X 18, 7/16 X 24, 1/2 X 20, 11/16 X 18. Ideal for fuel, oil, water, and air delivery, and for keeping the whole downstream system in one connection standard.

Benefits

• The odd port joins the AN system instead of dictating its own island of plumbing
• Sealing happens the way this thread standard actually works, not the way NPT habits assume
• Downstream, everything is familiar flares and familiar wrenches
• One correct adapter replaces a drawer of near-miss attempts

Features

• Port side: inverted (SAE 45 degree) flare connection, sizes 5/8 X 18, 7/16 X 24, 1/2 X 20, 11/16 X 18
• AN side: male 37 degree flare, 4AN, 6AN, 8AN
• Seals via the inverted flare's internal cone, a different geometry from AN's external 37 degrees
• Suits fuel, oil, water, and air delivery
• Sold as a single fitting

The Details

Thread standards differ in exactly one place that matters: where the seal lives. Here it lives at the inverted flare's internal cone, a different geometry from AN's external 37 degrees, while the AN side stays a dry metal-to-metal flare, no sealant ever. 45 degree inverted and 37 degree AN flares will thread together in some sizes and never seal; this adapter exists so nobody has to learn that with oil. Assemble the port side first, confirm it holds, then bring the AN plumbing to it with the body backed up by an aluminum wrench. When a port's identity is uncertain, measure before ordering: thread pitch gauges and calipers cost less than a stripped component, and the difference between tapered and parallel is visible in profile.

Kit Includes

• 1x Inverted Flare to AN Adapter (size per your selection)

Applications

• Port sizes: 5/8 X 18, 7/16 X 24, 1/2 X 20, 11/16 X 18; AN sizes: 4AN, 6AN, 8AN
• Common uses: adapting OEM and specialty ports to AN plumbing on fuel, oil, coolant, and air systems
• Mates to female AN hose ends in the matching size downstream