AN Fittings simplified. 

Unsure as to what AN fittings you need for your build? Is your cars fuel or oil system in need of a serious glow up? Or do you just want to gain a better understanding of these fittings and their function? Read our quick guide below to get yourself up to speed on AN Fittings. We stock a large range of OBP and JLS fittings instore. 

AN (Army-Navy) fittings are widely used in motorsport and high-performance applications for fuel lines and other fluid systems. They provide a reliable way to connect hoses and tubes together, and their sizing is crucial for ensuring proper flow and compatibility. Here’s our quick guide of AN fuel sizes and their specifications to help you work out what sizes you need for your fuel circuit. 

Ok, but what size hose do I need? 

-AN sizes are denoted by a number (e.g., AN4, AN6, AN8), which indicates the size of the fitting in sixteenths of an inch. The number corresponds to the inner diameter of the fitting or hose in sixteenths of an inch.  

Common AN Sizes and Dimensions: 

| AN Size | Diameter (inches) | Diameter (mm) | Common Use | 

1) AN6, 3/8", 9.53, Carburetors, fuel pumps 

2) AN8, 1/2" 12.7, Fuel injection, larger lines 

3) AN10, 5/8", 15.88, High-performance applications 

4) AN12, 3/4", 19.05, Race cars, large fuel systems 

Considerations when choosing the correct AN Size: 

1. Flow Capacity: Larger AN sizes allow for greater fuel flow, which is essential in high-performance applications where engine demands are high.

2. Compatibility: Ensure that the AN fittings and hoses are compatible with the system they are being used in. Mismatched sizes can lead to leaks or pressure loss.

3. Hose Types: AN fittings are often used with specific types of hoses, such as braided stainless steel or rubber, designed for high pressure and temperature. We stock both CPE and PTFE braided hose in our shop.

4. Fitting Types: AN fittings come in various styles, including straight, elbow, T-fittings, and more. Choose the appropriate style for your application to maintain a proper flow path. You can find all of our AN fittings here on our website: insert link

5. Material: AN fittings can be made from aluminium, steel, or stainless steel. The choice of material can affect weight, corrosion resistance, and durability.

6. Sealing Mechanisms: Many AN fittings use an O-ring or sealing surface to prevent leaks. Proper installation is crucial to ensure a tight seal.

7. Adapters: If you need to go from one size to another, we stock many adaptors as well which can get you from eg: AN6 to AN8 etc.

Understanding AN fuel sizes is vital for anyone working on their cars fuel system. The correct sizing and compatibility of AN fittings and hoses are crucial for ensuring efficient fuel flow and system reliability. Always select the appropriate size based on your specific application and requirements! Contact us to discuss sizes and if you need a line made up, our workshop team will be happy to help you! 

Written by Tiernan Fahy