what size fuel line should i use

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What size fuel line to use for an outboard?

Of course, it does! What Size Fuel Line To Use For An Outboard, 5/16″ or 3/8″? 5/16″ fuel line can be used in up to a 115 HP outboard engine. Anything above that has to be a 3/8″ fuel line.

Will increasing the fuel line size to ½” help?

Will increasing the line size to ½” help? Yes the pressure drop thru a ½” line is a nominal 5 feet versus 35 feet for the 3/8” id fuel line. The ½” line will result in a ½ pound drop versus the 3 pound drop for the 3/8” line at the stated flow of 83.3 gph (enough to support 1000 HP at a BSFC of .5).

When do you need a 3/8″ fuel line?

Like we said in the beginning, the 3/8″ line is required on anything that is larger than a 115 HP engine. Look at it like this. You can breathe through a straw.

How much power can a fuel line support?

The sizing of fuel lines is VERY IMPORTANT to those that are starting to push the limits of power on there cars or trucks. Understanding then how to size the supply and return line will be good information to know. For most applications the factory fuel lines have been able to support around 500 whp.

Where to put 100 micron fuel filter?

Why do you need an external fuel pump?

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Can a fuel line be too big?

If the diameter is too big: the lines will take longer to pressurize. If your pump can't maintain the pressure, it can drop during times of high demand, leading to engine damage. It is an unnecessary expense, bigger is more expensive.

How much horsepower will a 3/8 fuel line support?

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. The simple way to know is to install an electronic fuel pressure gauge. If the pressure falls as the engine RPM's go up you need more pump head.

What size are most fuel lines?

Typically, these 1/4" and 5/16" line sizes are in use for low flow or OEM systems, but are commonly used in high performance applications for pressure gauges as well as plumbing between the Regulator and Intake Manifold....FYI: Popular fuel line sizes:-6AN (=3/8" OD)-8AN (=1/2" OD)-10AN (=5/8" OD)-12AN (=3/4" OD)

What size fuel return line should I use?

The Fuel Return Line should be at least the same size, or one size larger than the supply. Make sure there are no sharp bends or kinks. The return line should direct fuel close to the bottom of the tank and away from the pickup.

Can I use rubber hose for fuel lines?

Rubber Hose Rubber fuel hose is easy to install. It is typically connected using standard barbed fittings and Fuel Line Hose Clamps. It must be rated for fuel or be labeled as meeting one of the following SAE grades: SAE J30R7 is carburetor rated fuel hose and should only be used in limited runs up to 50 psi.

What is the best material for fuel lines?

The best fuel line material depends on your needs. However, the best material for fuel lines is polytetrafluoroethylene or PTFE. PTFE fuel line is made of plastic material specifically known as Teflon. This fuel line material is impervious is resistant to the degenerative fuel effects which could form vapor barriers.

How much horsepower will 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.

Can I use compression fittings on fuel line?

I wouldn't be afraid to use them. They are normally steel (not brass) and use 2 compression sleeves. I have used them in fuel lines before without a problem. My 1/2 inch stainless main line has one stainless compression fitting in it and it has never leaked even after taking it apart many times.

What size fuel line do I need for 500hp?

Recommended MINIMUM Feed Line Size: 3/8" (or -6AN) up to 450 hp; 1/2" (or -8AN) up to 550 hp. The 383 I'm building will be in the 500-540HP range.

Why does a fuel tank have a return line?

It's primary purpose is to return excess fuel from the carburetor to the fuel pump, however it serves other important functions as well. Aside from providing a path for excess fuel to return to the tank, the fuel return hose also prevents vapor lock and over pressurization from occurring within the carburetor.

Does size of fuel line matter?

1:134:49Fuel Lines: Size Matters - YouTubeYouTubeStart of suggested clipEnd of suggested clipThe fuel filter is before the fuel pumps. And this is the inlet to the fuel filter it comes in fromMoreThe fuel filter is before the fuel pumps. And this is the inlet to the fuel filter it comes in from the aircraft tanks through the filter. Through there through there and up here to the fuel pumps.

What size fuel line do I need for E85?

For instance, an 8AN feed line and 6AN return line on a 1000 horsepower gasoline or race gas powered LS with 30psi is sufficient. However, on an E85 combo, we recommend a 10AN feed and an 8AN return minimum for the same setup minus the fuel change.

What size is rubber fuel line?

x ½-Inch O.D. for Small Engines 25-Foot Length.

Do you need different fuel lines for E85?

It can be harmful to fuel lines, fuel pumps, and other fuel system components that aren't resistant to ethanol. So if you have a 1993 or older vehicle that still has its original fuel system, you may not be able to use E85. If your 1993 or older vehicle has a newer fuel system, it should be OK to use E85.

Fuel Line Size and HP Rating | Factory Five Racing Forum

FFR4398. Powder coated chassis, pin drive IRS, custom side pipes, custom 289 FIA features, all aluminum 4.6L DOHC with Twin Turbos, Tremec TKOII, and lots of other goodies.

fuel line sizes vs hp and fuel volume | Factory Five Racing Forum

I appreciate all the answers and opinions, I have learned alot from the forum members here. I decided to remove my fuel lines and replace them with 3/8 feed and return, just because that's what Fitech has designed their system to operate with.

Fuel line size vs. Horsepower - Don Terrill’s Speed-Talk

MadBill wrote:It's more a matter of acceptable pressure drop.There's only one/two/four needle/seat orifices, but the line has flow resistance per foot, plus that of the fittings, which can vary from not bad to horrible (I have heard a drilled 90° creates as much restriction as 10 ft. of hose.) Check any good fuel pump mfgr's site for data on this.

What is the A2 hose used for?

A2 Hoses: Are used for the fuel tank vent hose below the deck. They aren’t designed to have fuel sitting in the hose but do have a fire-resistant covering on the outside of the hose. B1 Hoses: Are used for feeding fuel from the boat fuel tank to the fuel filter bracket BUT ABOVE THE DECK OR NOT ENCLOSED!

What is the difference between a B2 and A1 hose?

They are basically the same as the A1 hoses but do not have the fire-resistant covering that is on the outside of the hose. B2 Hoses: Are used for the fuel tank vent hose BUT ABOVE THE DECK OR NOT ENCLOSED! Basically the same as the A2 hose but without the fire-resistant covering on the outside of the hose.

Why is my fuel pump running lean?

If the fuel pump is sucking in air every time it tries to get fuel, it will aerate the fuel and run the engine lean. Giving you all kinds of different problems!

How to know what fuel line is on a combustion engine?

The basic functionality of a combustion engine and the fuel demand for the horsepower is the same! You will also know what fuel line is supposed to be there by looking at the hook up on the engine. Wherever you hook up the fuel line on the engine there will be a hose barb. If it is a 5/16″ or a 3/8″ hose barb, that is what you should use.

What is the difference between a 5/16 and 3/8 fuel line?

We get it. But there is a little more to it than that. The 5/16″ fuel line is actually perfect for smaller outboards. Being a little smaller than the 3/8″ hose, it works great for little kicker motors, and sailboat outboard engines.

What fuel line do you need for a Honda engine?

The general rule of thumb still stands regardless of what manufacturer engine you have! Whether it be Honda, Mercury, Yamaha, Suzuki, Tohatsu, Nissan, or Johnson/Evinrude. Any engine that is above the 115 HP requires you to use a 3/8″ fuel line! The basic functionality of a combustion engine and the fuel demand for the horsepower is the same!

Why is it important to have a fuel line installed?

Going back to the straw theory, having the correct fuel line installed will help ensure the proper fuel consumption for the engine. Thus, keeping up and even prolonging the life of the engine. You don’t want to cause premature failure of the engine or any of the components that are in the fuel system.

What is the minimum feed line for an E85?

For instance, an 8AN feed line and 6AN return line on a 1000 horsepower gasoline or race gas powered LS with 30psi is sufficient. However, on an E85 combo, we recommend a 10AN feed and an 8AN return minimum for the same setup minus the fuel change. We also like to take into account your future goals, and whether you order these lines and components from us, we suggest you do as well!

How much methanol does a gasoline engine use?

Methanol fuels use approximately double the amount of fuel of gasoline to reach a target power level. In the event that you are using Methanol in replacement of an intercooler (commonly referred to as running the engine "wet") you may use even more Methanol.

Can I undersize fuel lines?

Can I undersize fuel lines? Yes, not just the feed line, but the return line must be large enough to not only flow the required amount to feed the engine, but the return line is important for allowing a fuel pressure regulator to effectively do its job.

How many whp is a stock fuel line?

Up to 500-550 whp: Stock Fuel Lines

How many whp can a fuel line hold?

For most applications the factory fuel lines have been able to support around 500 wh p. There are variations to this based on each vehicle and the fuel being used. For example if using E85, which requires 30% more fuel to reach stoic conditions, you would need to size the fuel lines even larger. If unfamiliar with ethanol based fuel, be sure to check out our article here on ethanol-based fuels.

Why is the return fuel line smaller than the supply line?

The reason for this is that the return line will always flow less fuel being that the motor is using a portion of the supplied fuel to burn and run the motor. Things look for when buying fuel line .

Is methanol good for fuel lines?

Many users today are discovering the benefits of using ethanol based fuels or methanol. While these fuels are great, not all fuel lines are rated to withstand their corrosive properties. Therefore it is important when purchasing fuel lines that you are realistic with the fuels you MAY end up running in your vehicle.

What is fuel line?

Fuel line is a petroleum-resistant nitrile tube with a covering that resists weathering, ozone and heat and can be used for ethanol-laced fuels and diesel fuel. It should, however, not be used on coolant systems, oil systems or fuel-injection systems that produce pressures higher than 50 psi.

What is the rating of marine fuel hose?

Marine hose must have the SAE J1527 Style R1 rating emblazoned on the hose to pass as seaworthy. Marine hose is rated for 40 psi and will work in a pinch for carbureted passenger cars and light trucks.

What is a high pressure fuel injection hose?

This fuel hose is SAE 30R9-rated and uses a fluoro elastomer inner liner that will withstand up to 180 psi and 300 degrees. It is approved for all fuel blends including straight methanol, and the outer coating is also ozone- and abrasion-resistant. High-pressure fuel-injection hose can also be used in low-pressure applications, but the difference in pricing may convince you to save it for where it is needed.

What is the hose from fuel cell to filter?

The main line from fuel pumps to regulators (under hood) is a single neoprene 1/2 id hose. I do not see any deterioration, other than some contaminants in filter and carburetor float bowls.

What temperature can a fuel hose withstand?

When a bent filler neck hose is necessary, wire-inserted fuel hose is also offered. It bears the SAE 30R5 rating and can withstand temperatures of -40 to 212 degrees. Working pressure is not relevant, but wire-inserted hose can withstand 50-85 psi, depending on diameter.

How much water can an E10 hold?

E10 for instance, can hold up to 4 teaspoons per gallon before any separation or problem occurs. The more ethanol you have, the more water you could hold without issue. However, if you have more than 4 teaspoons per gallon from condensation you have a bigger problem like the fuel cell cap being faulty.

Is methanol hose ozone resistant?

It is approved for all fuel blends including straight methanol, and the outer coating is also ozone- and abrasion-resistant. High-pressure fuel-injection hose can also be used in low-pressure applications, but the difference in pricing may convince you to save it for where it is needed. Nylon fuel line.

What line does a Holley truck have?

All factory big blocks got 3/8" line. Holley equiped cars had a single 3/8" feed, Q-Jet cars got a 5/16" return line. You can get the 3/8" sending unit rather inexpensive, very easy to drop the tank and replace it.

Is a 5/16 sender better than a 3/8?

The fuel line length, diameter, material composition, number of bends and number of fittings can all act as restrictions. So a 3/8 line will still be better than a 5/16. K.

Where to put 100 micron fuel filter?

We recommend you install a 100 Micron In-Line Fuel Filter between the tank and the pump.

Why do you need an external fuel pump?

However, when using an External Fuel Pump, you can starve it for fuel if the line is too small.