The holidays are here! As we celebrate our 11th year in business, take a look at the sales we have going on for this year! Retail customers can save 15% on all orders! Just use code: holidays2026 Wholesale dealers stocking up for the upcoming racing season can save extra on orders over $1000 with this code: […]
As FLF continues to grow, so does the functionality of our website! First up is the new Account Tools menu, this gets you fast and easy access to the menu items in the “My Account” page on a PC. Reorder Any Order You can now reorder previous purchases directly from your Orders page. Instantly move […]
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 […]
FLF’s Remote Oil Filter Mount allow you to relocate your oil filter to a more convenient part of your engine bay. Our unique and compact 4-port design allows you to have multiple ways to easily orient this product with different flow paths. You can also use the unused ports for sensors, turbo oil feed, and […]
If you’ve been looking for a way to achieve a professional, show-quality finish while protecting your lines, this is the solution. Our separators are CAD-designed and manufactured from an extremely durable, temperature-resistant polymer, engineered to withstand the harsh environments of an engine bay or undercarriage. Why Choose FLF Snap-In Separators? Keep your build organized and […]
Due to popular demand, we have extended our Spring Sale through the end of April. We’ve also expanded the sale to include free Hose Cutting Shears for wholesale orders over $1000. Take advantage of this deal until April 30th! COUPON SPRING2026 – 10% OFF ALL RETAIL ORDERS OVER $300 COUPON SPRING2026WH – Free AN Double-Sided […]
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 […]
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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"
7/16-20
Fuel return, turbo feed, nitrous
-6AN
3/8"
9/16-18
Primary fuel EFI feed/return, trans coolers
-8AN
1/2"
3/4-16
High HP fuel, oil coolers, power steering
-10AN
5/8"
7/8-14
Remote oil filter, turbo drains, breather lines
-12AN
3/4"
1-1/16-12
Large dry sump oil lines, high-flow coolant
-16AN
1"
1-5/16-12
Radiator coolant hoses, high volume dry sump
-20AN
1-1/4"
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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