LS Fuel System

[Nova_Cobra64]

As promised, this is the start of what I hope to be a comprehensive guide to fuel systems for the LS engine swap. As of right now this FAQ is not complete. I hope to obtain as much input as possible from members with successful LS swaps with regards to their fuel system components and part numbers.....so if you are one of those members, your help would be much appreciated. Lets try to make this easier for the next guy. That said, I would very much appreciate that for organizational purposes rather than replying in this thread, you submit any contributions to me through private message as that will allow me to group all related information together. I will be sure to give each member credit for their contributions.

[Nova_Cobra64]

Part 1 - Basic fuel system requirements

The first step to getting started on your fuel system is first determining what you have. The LS fuel system has specific pressure requirements, which means the fuel pressure is regulated and unused fuel supplied by the fuel pump is going to be returned to your fuel tank. As such, you are going to need a fuel tank that will be able to accept fuel return. There are two types of fuel systems from the factory. The first type is equipped with internally regulated fuel rails. In this case there is a second connection on the fuel rail for the return fuel. The second type will just have one connection on the fuel rail, and this system requires the fuel to be regulated at 60psi within your fuel supply system. The components and specifications of both systems are identical with the only difference being the addition of the regulator in the second type of fuel system mentioned. I will post a basic overview of the parts needed to build your fuel system now, specific part numbers will be added in Part 2.

Fuel Pumps - Your fuel pump will need to put out a minimum of 60psi at a rate of flow that is going to vary by application (ie: 40 gallons per hour for the LS3 and 50GPH for the LS7). The fuel pump can be either an in-tank or external in-line pump. While it could be subject to disagreement, there is no "best" route. Both systems have their benefits, such as the in-tank pumps being said to last longer due to being cooled by fuel or the external pumps being easier to change if the need arises. The option does exist to replace stock in tank pumps with one meeting your system's requirements, information on this will be included futher in this guide. If the factory sender does not have provisions for an in-tank more often than not an in-line pump will be used for the sake of simplicity.

Fuel Filters and Regulators - For those who need to build a fuel system regulated to 60psi, the most cost effective method is running Corvette filter/regulator (GF822, jobbers available). The GF822 will regulate your fuel system to 60psi and is equipped with a 3/8" male quick connect for fuel in, 3/8" female quick connect for fuel out, and a 5/16" male quick connect for the return fuel. Because this filter has to be placed after the fuel pump, some people opt to install a fuel filter prior to the fuel pump for added protection and extended life of the more expensive filter/regulator.

Fuel Lines - Because your fuel system is going to be running upwards of 60psi, you are going to want to make sure that any fuel lines and fittings being run after your fuel pump are going to be capable of handling such pressure. From there it comes down to personal preferance. Steel, stainless steel, and aluminum hard lines with -AN style fittings are one option. If you go this route, there are 2 items to note. The first is that -AN style fittings require a 37 degree flare, a basic flare tool can be had for around $30 and making the lines is as simple as anything else you will experience in the swap. The second note is if you opt for stainless hardline, the flare tool required is significantly more money ($250+). Braided style hoses are the other common type of hose used for LS swaps. There are interal and external braided hoses available in a variety of colors that are also very easy to make. The manufacturers of these hoses all offer fittings that work specifically with their lines. I've seen some mention of guys having used nylon fuel line (which is pretty common from the factory now), and some having used fuel injection rated rubber hose with fuel injection clamps. The use of basic fuel injection hose and clamps is generally not preferred due to safety concerns. Further to this I've read there are NHRA restrictions on barbed fittings and rubber hose, if anybody can clairify this please PM me.

Fittings As mentioned above, the use of -AN style fittings is extremely common with LS swaps. -AN is a unit of measurement where -01AN = 1/16", so as an example -06AN is for 3/8" line. -AN fittings come in a variety of colors. JIC fittings are also 37 degree and can be used as a cheaper alternative but will not come in any special finish. The 3/8" and 5/16" style quick connects for fuel supply and return are available from a variety of manufacturers to work with -AN fittings and with nylon line as well. One item to pay attention to while assembling a fuel system with -AN fittings is many pumps and filters have metric and NPT threads and will require fittings to cross over.

Misc Items There are some small items to consider as well while you are building your fuel system. You will want to make sure to order the necessary supports for your fuel lines or hoses. A fuel shutoff valve can also be included as a theft precaution or to make your life a little easier while changing fuel filters.

[Nova_Cobra64]

Part 2 - Part Numbers

In this section I hope to make a list of parts that are either commonly used or compatable/meeting the requirements of an LS swap.

Corvette Fuel Filter/Regulators - AC Delco GF822, WIX33737, Napa NGF3737.

External In-Line Fuel Pumps - Carter GP5000, Trick Flow 25004, Airtex E8248, Walbro 255 (do not have specific # at this time)

In Tank Fuel Pumps - Walbro 255 (do not have specific # at this time)

Fuel Lines - Due to there being so many hose options to be ordered rather than list specific part numbers I will work on listing manufacturers and styles of hose rated to handle fuel injection pressures.

Russell - Proclassic, Prorace, Twistloc, Aluminum hardline.

Fuel Fittings - Same deal here as the fuel lines, with the exception of the common quick connect fittings and oddball hard to find stuff.

3/8" male quick connection - Russell 640940 (to -6AN male), Aeromotive 15104 (to -10AN male)
5/16" male quick connection - Russell 640930 (to -6AN male)
3/8" female quick connection - Russell 640850 and 640853, Jegs 555-103101, Fragola 491989 (to -6AN male), Dorman 800-121 (for nylon line).
5/16" female quick connection - Russell 640860 and 640863, Jegs 555-103100, Fragola 491990 (to -6AN male), Dorman 800-120 (for nylon line).

[Nova_Cobra64]

Part 3 - Examples Of Complete Installations

Ok, I'll get this section started with the fuel system I have purchased for my truck. Keep in mind this system has not been function tested yet, but with the research I've done I see no issues with it. I did not buy either of the filters from jegs, but I priced them there for simplicity. These parts are essentially in order from fuel tank back with the exception of the aluminum line which I just listed as a whole coil as well as the tube nut and flares, through I intend to install line between each component. All the pieces in this system are either black or endura finish. I opted for this setup as in my personal preferance I don't really care for the fuel lines to be noticeable, but I still wanted a clean quality setup.

Jegs 20 gallon aluminum fuel cell w/-8AN fittings (555-15345) - $249.99
Jegs fuel cell mounting straps (555-15349) - $32.99
Russell -8AN to -6AN reducer (799-660021) - 2 @ $15.99 = $31.98
Russell 3/8" black coated aluminum line good for 250psi (799-639253) - $72.99
Russell tube nuts 2pk (799-660571) - 5 @ $3.99 = $19.95
Russell tube sleeve 2pk (799-660651) - 5 @ $3.99 = $19.95
AC Delco GF822 for prefilter (037-GF822) - $21.99
Russell 16x1.5mm to -6AN male to fit GF822 (799-670531) - 2 @ $13.99 = $27.98
Jegs 255lph fuel pump (555-159001) - $129.99
Russell 10x1mm to -6AN male fittings for fuel pump (799-670481) - 2 @ 12.99 = $25.98
Jegs 3/8" FI female quick connect to -6AN male for filter supply line (555-103101) - $15.99
Jegs 5/16" FI female quick connect to -6AN male for filter return line (555-103100) - $14.99
AC Delco filter/regulator (037-GF822) - $69.99
Russell 3/8" FI male quick connect to -6AN for filter out to fuel rail (799-640940) - $13.99
Jegs 3/8" FI female quick connect to -6AN for fuel rail (555-103101) - $15.99
Russell 3/8" cushion clamps 10pk (799-650980) - 2 @ $6.99 = $13.99
Jegs 37 degree flare tool (555-80084) - $29.99
Jegs -6AN wrench (555-80551) - $10.99

Total is $819.71 for this setup through jegs.

[Nova_Cobra64]

Part 4 - Related Diagrams, Tutorials, And Links

Install using a factory tank, external pump and Russell Proclassic hose.
http://www.classictrucks.com/tech/09...all/index.html

Tanks Inc in tank pump setup with install information linked at the bottom of the page.
http://www.tanksinc.com/index.cfm/pa...prod/prd84.htm

An example of modying a stock tank for newer style pump/sender.
http://www.cardomain.com/ride/716267...elta-88/page-3


An example of an LS1 sender in a stock style tank.
http://www.vetteworksonline.com/ls1_conversion_fuel.htm