New product at FLF! Our Heat Shrink Sealing Tubes help to seal our Heat Protection Sleeves against the fitting or other component, helping to prevent heat or other elements from entering the sleeve and helps to keep things in place. Available in 1-foot roll sizes for any project, with longer bulk rolls to be made available soon!
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TRACK TESTED & PROVENRated for high PSI, high temps, and track performance
RACER TECH SUPPORTCall (866) RACE-561 for service
TECHNICAL GUIDE
AN Thread & Hose Sizing Reference
AN (Army-Navy) thread sizes are the motorsport standard for high-pressure fuel, oil, and coolant plumbing. Use this quick reference to select matching fittings, hose sizes, and adapters for your build.
AN Size
Hose ID / Tube O.D.
Thread Size (SAE)
Typical Track Applications
-4AN
1/4 inch
7/16-20
Fuel return, turbo oil feed, nitrous
-6AN
3/8 inch
9/16-18
Primary fuel EFI feed/return, trans coolers, power steering
-8AN
1/2 inch
3/4-16
High HP fuel, oil coolers, power steering
-10AN
5/8 inch
7/8-14
Remote oil filter, turbo drains, breather lines, very high HP fuel systems
-12AN
3/4 inch
1-1/16-12
Large dry sump oil lines, supercharger coolant systems, extreme HP fuel systems
-16AN
1 inch
1-5/16-12
Radiator coolant hoses, high volume dry sump, extreme alcohol-fueled engines
-20AN
1-1/4 inch
1-5/8-12
Large radiator coolant lines, high-capacity dry sump scavenge
Need custom plumbing advice for your turbo, dry sump, or fuel cell? Call our track support team at (866) RACE-561.
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