Contents
- 1 What size fuel line do I need?
- 2 Is 3/8 fuel line big enough?
- 3 Can a fuel line be too big?
- 4 Are bigger fuel lines better?
- 5 What size is 8AN fuel line?
- 6 Is fuel line measured ID or OD?
- 7 What is the ID of 3/8 fuel line?
- 8 Is 6an the same as 3 8?
- 9 Can a fuel line be to small?
- 10 What is the best material for fuel lines?
- 11 Does a fuel return line have pressure?
- 12 How much HP will a 5/16 fuel line support?
- 13 Which fuel line is the return line?
- 14 Does size of fuel line matter?
What size fuel line do I need?
Recommended Size, Based on Horsepower
| Recommended Fuel Line Size (from the tank to the pump) | ||
|---|---|---|
| Engine Output | Size (inches) | Size (AN) |
| 350-450 hp | 3/8 in. | -6 |
| 450-650 hp | 1/2 in. | -8 |
| 650-1,000 hp | 5/8 in. | -10 |
1
Is 3/8 fuel line big enough?
A 3/8 ”id fuel line can easily support 600 HP given sufficient “pump head”! Given a big enough pump a 3/8 ” steel line could support 1000 HP. If the pressure falls as the engine RPM’s go up you need more pump head.
Can a fuel line be too big?
The fuel line size being too large won’t really affect the fuel pressure. Excessive fuel pressure is what can cause the fuel to overrun the needle/seats and flood the motor with excess fuel. That being said running a -8AN fuel line is beyond overkill for a 340 but it shouldn’t adversely affect it.
Are bigger fuel lines better?
The bigger a pipe, the higher potential volume. Raising pressure does not increase volume, the opposite actually happens. When you buy a fuel pump, look for the flow rating at specific pressure, as some will mislead you by stating flow rate at zero psi.
What size is 8AN fuel line?
The Good News
| Male Thread Size | AN Size * | Equivalent Tube Size (Nominal OD) |
|---|---|---|
| 7/16-20 | 4AN | 1/4″ |
| 9/16-18 | 6AN | 3/8″ |
| 3/4-16 | 8AN | 1/2″ |
| 7/8-14 | 10AN | 5/8″ |
3
Is fuel line measured ID or OD?
Tubing is OD ( outside diameter ) and Pipe is ID (inside diameter). So the easiest way to tell the size of your fuel line, which is tubing, is to use a combination wrench. Whichever one slips over snuggly is the winner.
What is the ID of 3/8 fuel line?
So the easiest way to tell the size of your fuel line, which is tubing, is to use a combination wrench. Whichever one slips over snuggly is the winner. What is the outside diameter of 3/8 fuel line?
| AN Size | Tube or Hose OD | Tube or Hose ID |
|---|---|---|
| -5 | 5/16” | .062” |
| -6 | 3/8 ” | .297” |
| -8 | 1/2” | .391” |
1
Is 6an the same as 3 8?
No they aren’t exactly the same. Most people compare them because they are close and flow roughly the same. According to this, AN and hard line are OD measurements and NPT is inside diameter so for AN and hard line the inside diameter would depend on the thickness of the tubing.
Can a fuel line be to small?
Return line should always be at least one size smaller than supply line, otherwise you’ll starve the pump.
What is the best material for fuel lines?
The best solution is a material called PTFE. That stands for polytetrafluoroethylene —a plastic material that is best known as Teflon in one specific variation. This material is impervious to the degenerative effects of fuel that also creates a vapor barrier so fuel vapors cannot leak past.
Does a fuel return line have pressure?
In return -type systems, fuel is returned at a lower pressure than that found in the feed line or fuel rail. These can be replaced and upgraded as required. These regulators work by allowing the line pressure to build to a level higher than normal line pressure before venting excess pressure back to the tank.
How much HP will a 5/16 fuel line support?
If you’re just cruising around with a carbed SBC, you’ll probably be fine with a 5/16 ” line up to about 500 HP because you’ll never tax the system enough to starve the motor of fuel.
Which fuel line is the return line?
The vapour- return line normally runs from the fuel pump or the fuel filter to the fuel tank. This vapour- return line is connected to a special outlet in the fuel pump. Any vapour that forms in the fuel pump returns to the fuel tank through this line.
Does size of fuel line matter?
Does size really matter when it comes to fuel lines? According to the fuel delivery system experts at Fuelab, it does. It’s because fuel line size and length have a direct effect on the amount of fuel pressure drop your fuel system will experience.