This article will explain the an standard and explain how our stainless steel lines and an fittings meet the specification perfectly as do most of the an fittings and stainless steel lines sold by our competitors. This example compares 6an and 8an supply fuel lines both are 14 long.
1966 Mustang Fuel Line Routing And Type Ford Mustang Forum
An fuel line size. Inside the ½ fuel line the fuel would be traveling at 2 ftsecond and inside the 38 fuel line just over 3 ft per second. The ½ line will result in a ½ pound drop versus the 3 pound drop for the 38 line at the stated flow of 833 gph enough to support 1000 hp at a bsfc of5. An fittings and stainless steel lines. Sizes for rigid tubes were already standardized with sizes called out by tubing od 316 12 etc. What size are they really. 6an 38 od 8an 12 od 10an 58 od 12an 34 od.
Can you see the confusion starting. The amount of pressure drop we can expect for 14 fuel lines at 110 gph is. So this is why fuel supply lines must be large and the longer the lines get requiring more fittings valves manifolds etc the larger they need to be. Yes the pressure drop thru a ½ line is a nominal 5 feet versus 35 feet for the 38 id fuel line. The same steps can be used to measure other types of tubing such as those for brake lines. Vac lines are smaller.
The stock carb petcock is 516. The an size number is correctly displayed with a dash before the number. An 8mm line with say a 14 id will flow that with only a 4 psi drop. All the fuel fittings and lines are 516. Put big expensive lines on the car if it makes you feel better but it wont effect how the car runs one bit. And since the fuel regulator is at the other end that isnt shit.
The size of the fuel line is determined by the outside diameter. The pressure drop at 1320 hp thru a 38 steel line might be around 5 psi. Sometimes we encounter some confusion about the an specification. An hose sizes were designed to match the id sizes of these rigid tubes. Popular fuel line sizes. Commonly called a feel good mod my back ground in fluid power really is a bitch to live with.
Referring to graph a. Taking this information into consideration lets examine how different fuel line sizes can affect pressure drop. Completing the measurement is simple and takes relatively few tools. For example an an size 2 designates a tube od of 18 2 x 116 the tube od of an size 3 is 316 3 x 116. Acerbis petcock is 516. The idea behind an hoses and an fittings was to provide a flexible alternative to rigid tubing in plumbing systems on aircraft and military vehicles.
Gallery of An Fuel Line Size
