Effective immediately, all users now have the ability to save their carts for later retrieval. You can also share carts via a link and allow another user to add the items from your saved cart to their own cart. This feature allows you to share parts lists with friends or customers. When a cart is […]
Streamline your plumbing with the FLF Bulkhead Mounting Flange—the cleanest solution for securing AN bulkhead adapter fittings to firewalls, panels, or any flat surface. Engineered to eliminate clutter and simplify installation, this flange allows for direct threading, removing the mandatory requirement for a secondary backing nut. These are especially useful when you have difficulty accessing […]
Retail customers can save 10% on orders over $300 SPRING2026 FLF Dealers can get a free complete set of AN Double-Headed Wrenches with any stocking order over $1000 with code: SPRING2026WH Coupons expire 2026/3/31, so get on it while you can!
We’ve received many requests for this feature, and now we’ve finally added it to our website! This handy tool will allow you to save lists of products on the FLF website to make ordering and re-ordering MUCH easier! This is especially handy for shops that work on many of the same types of vehicles and […]
FLF’s premium headgear features the high-performance innovation that you expect from FLF. Cutting-edge ventilation keeps your head cool during those hot afternoon drift sessions, the visor shields your eyes from the sun’s glaring rays, and the prominent FLF logo lets everyone know that you put the best damn fittings and hoses on your racecars. FLF […]
Check out this handy new product from FLF! This Hose Guide perfectly routes your hoses in a 90 degree bend at exactly the minimum bend radius. Helps to eliminate hose sag and relaxation when they’re at rest, keeping them turned at their intended routing. Also helps to prevent kinking or reduced flow from being bent […]
Alright everyone, 2026 ready to go! Get ready for this new year with a fresh set of fittings and hoses from FLF Racing Supply! Whether you’re a weekend racer working on your project car over the winter or one of our stocking dealers, now is a great time to prepare for racing season! Check it […]
Merry Christmas, everyone!Check out this year’s holiday deals: Retail customers can save 15% on all orders with this code: MERRYCHRISTMAS Wholesale customers can get an extra discount on orders over $500, just use the following code at checkout: HOLIDAYWHOLESALE If you’re placing a stocking order over $2000, you can qualify for a bigger discount with […]
Selecting the right type of hose for your application is incredibly important for ensuring proper performance and reliability. Picking the wrong hose can result in leaks, poor performance, reliability problems, or in extreme cases, a very serious fire. This detailed guide will assist you with selecting the right hose for your application. We carry multiple […]
We’ve received requests for counter displays for some time, and now we’re delivering. We didn’t just want to do something boring, like a sheet of paper with some graphics sandwiched between some sheets of plastic. No, we wanted something that will stand out. This sign is fully 3D printed and features an actual -10 90 […]
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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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