Enter The 2023 LS Fest West Trip Sweepstakes Today And Join Us In Las Vegas! So there needs to be a transition to the smaller return size somewhere. Stay Updated with Emails from Summit Racing. Simple math. The main challenge is getting it learned but once she has learned the table this is a awesome kit. Results 1 - 25 A 5/16-inch return line is usually adequate for fuel pumps that flow 255 LPH of fuel or less. A -5 is hard to find. Only 4 Wiring Connections Required! Estimated International Ship Date: ( 35 ), Ignition Boxes, Sniper EFI HyperSpark CD Ignition Box, Capacitive Discharge, Digital, Black, Each, 4.46 out of 5 stars I only have a 100 miles on it but has been good so far as this is my daily driver. I had one of the kits had the IAC motor fail but they sent me a new motor with no problems. Help support me by using the links below. Its been all smiles driving the Blazer now. The included Genuine Bosch LSU 4.9 Wideband Oxygen Sensor provides realtime Fuel Map Learn! . the install was relatively easy other then a few issues with it being a marine application. Transmission provisions on throttle lever for TH350/TH400 and 200R4/700R4, Fits most stock Rochester Quadrajet (Q-Jet) air cleaners, Brake Booster adapter included, if required, Universal Throttle and transmission kickdown bracket included. Part# 12-886. Being a boosted engine, it will require some laptop tuning to get the calibration dialed in 100%. Fuel Pressure Regulator: The majority of Sniper EFI systems come with a pre-installed fuel pressure regulator that will work great for all naturally aspirated, nitrous and roots supercharged applications. ( 10 ). Option 1: stock 3/8 pre-bent and adapting 6AN on either end (Classic . Much more quite ride. The Sniper EFI throttle-body drops in place of your . Guaranteed lowest price! 7bar (735kPa) up to 102.9 PSI of Boost. Sniper EFI Air Cleaner Drop Base - Chrome. Learn how to download and update your Sniper EFI software. Figured that out and bang, off and running. Holley In-Tank Retrofit Fuel Module - 255 LPH, Holley In-Tank RetroFit Fuel Module-Returnless Style, Sniper EFI Air Cleaner Drop Base - Chrome, Sniper Air Cleaner Assembly, 14" x 3" - Black Finish, Holley Strip Dominator Intake - Big Block Chevy V8. 03-25-2017, 02:47 PM. Bangshift.com: The Caddy Powered C10 Gets A Holley Sniper EFI, RacingJunk.com: Installing Holley's Sniper EFI System, FullSizeBronco.com: Holley Sniper EFI Install, Compatible w/ Holley EFI, Sniper EFI, and Terminator X Software, Replacement Sniper and Terminator X O2 Sensor, Earls - 1/8" NPT in Hex The core of this kit is great, the install is not as intimidating as it might seem; however the videos created by Holley and uploaded on this site misrepresent what is actually in the kit, be aware that you will not receive any throttle linkage components or connectors as stated. ( 13 ), Plumbing Kit, Push Lock, -6 AN, 25 ft. This kit does come with a returnless style fuel module, so no you either don''t need this kit, or you can simply not run fuel through your current return line. A Sniper EFI system requires the use of 100 micron pre-filter and 10 micron post-filter. I have installed 3 EFI systems from another company F*t**h. They all had issues even on stock to mild engines and a pain to tune using there supplied handheld. Buy It Now. ( 5 ), Fuel System Plumbing Kit, Fuel Pump to Carburetor, -6 AN Braided Flex Line, 3 ft. Instructions are super easy to follow and complete for all set-ups. 2023 Holley Performance Products, Inc. All Rights Reserved. I'm planning on using the Holley Sniper EFI though haven't seen a ton of feedback on it yet. Holley Sniper EFI - Stock . installed the master kit on my camaro .. went pretty smooth .. just over 5 hours start to finish .. works great . View Part. Stay up to date with the latest releases, events, promotions and more. I am not sure at what point they stopped providing these parts in the kit it was just something I did not expect to chase down after getting into the install (Holley you should put some notes on your install videos indicating that the linkage parts / brackets and electrical connectors are no longer provided). ME4NSTRK69. It runs so much better, and stronger than it did with the 390 carburetor that I took off it. Introducing Sniper EFI Master Kits, with a Returnless Retrofit Fuel Module. Fuel injection can be daunting after a life of tuning carburetors, but Sniper EFI is arguably one of the simplest to install systems available on the market. We recommend these similar substitute parts: 4.5 out of 5 stars Copyright 2022 Holley Performance Products, Inc. All right reserved. The innermost Primary Barrier Layer offers high resistance to heat and aggressive fuels. KIT INCLUDES: [4] Hose End, Vapor Guard, Straight, 3/8 in. Holley EFI fuel kits are the perfect addition to your Sniper EFI or Holley EFI kit. of 195, Fuel Line, GM LS, Push Lock Type, -6 AN Diameter, 25 ft. Length, Kit, 4.16 out of 5 stars This part is legal for sale or use on Racing Use Only Vehicles. ( 8 ). Will the stand behind it if it has problems 1000% yes. ( 2 ), Distributor, HyperSpark, Hall Effect, EFI, Billet, Black, V8, Small Block Gen I, Big Block Mark IV, Chevy, Each, 4.2 out of 5 stars We hope that you will agree. It incorporates an internal fuel regulator and is easily set up with an included full-color touchscreen display. 1050 Ford Street, Colorado Springs, Colorado 80915-2909. Also pre plan how you will mount the fuel pump and filters, these need to be mounted close to the fuel tank a lowest level and Holley can't solve that for you as every car is different; this was expected on my end just a heads up. This is the original 1979 350ci small-block. Injectors, Kit, 4.88 out of 5 stars It also uses a single fuel injector and is ideal for older four and six-cylinder engines. Holley just brought EFI within range - introducing Sniper EFI! c tng c thi ua. ( 21 ), Fuel Injection System, Stealth, 4150 Flange, Polished, up to 650 hp, 870 cfm, Four 100 lbs./hr. Where should it be? Are you waiting to convert your carbureted vehicle to Sniper EFI, but don't like the idea of mounting an external fuel pump? No need to mount an external fuel pressure regulator! In addition to your Holley 2300 Sniper Kit you will want to order the 12-130 HOLLEY IN-TANK RETROFIT FUEL MODULE $501.95. Today, Fuel Injection System, Holley Sniper EFI, Self-Tuning, Master Kit, Polished Throttle Body, Kit, 4.36 out of 5 stars The sniper master kits ship with OEM grade 255 LPH Walbro Pumps. Sure enough, they did, I WILL ONLY BUY HOLLEY PARTS FROM HERE ON OUT. ( 23 ), Estimated Ship Date: t iscriticaltousehigh pressureclamps orAN fittingstoreducethepossibilityof afuelleak. Mar 15, 2023 The middle Earl's Vapor Guard Barrier is a Thermoplastic layer that provides superior fuel isolation and virtually eliminates vapors from escaping through the hose. Setting the throttle position and response was a little difficult for me and the instructions didn't seem very clear, but that could just be my fault. OEM Style TPS/IAC and Fuel Pressure regulator, for years of dependable service. I've had mine installed on my 1984 CJ7 with a 4.6 Newcomer Racing engine for about a year now. It's the 2300 2 barrel self learning kit. Sniper EFI throttle bodies require 58-60 psi of fuel pressure and a 10 micron filter. You will need to add your own lengths of 3/8-Diameter fuel line. After installing the Sniper and running for a few weeks with the initial air/fuel settings as mentioned, I saw roughly 1 to two-miles per gallon increase. Join the Holley Family. What are recommended options for fuel line? Do I still need the holley 12-753 30 amp relay . ( 3 ), Fuel Injection System, Master Kit, Stealth, 4150 Flange, Black, up to 650 hp, 870 cfm, Four 100 lbs./hr. They are engineered using Holley fuel pumps, regulators and filters coupled with quality Earl's plumbing to provide a fuel system tailored to the needs of your EFI System. The secret to Earl's Vapor Guard hose is in its layers. Please note that Checkout Prices will be in US Dollars. - NO laptop required! We choose Earl's Vapor Guard EFI Hose . 20 feet of 3/8" EFI Hose, in-line fuel pump, post and pre fuel filters, return bulkhead, and all of the necessary fittings and hardware. The head flow right at 300. Self-tuning ECU means you dont have to be a computer/tuning wiz to have EFI! This site uses cookies to offer you a better browsing experience. I just purchased a Holley Hyperspark Distributor, CD box, and coil. Diameter, 15 ft. The 12-270 supports over 1000 hp Compatible with Gasoline or E85 . Never miss a sale on new parts, tools, and more! Monday 3/6/2023 Need a dual-feed fuel line for your Sniper or Terminator X Stealth throttle body? If this works as well as I hope it does, I look forward to purchasing another for my 65 malibu. Patent Number - US10294902B2. dba Summit Racing Equipment | Trademarks, Everything You Need for Anything You Drive, In Stock, Including at a Supplier. You will need to add your own lengths of 3/8-Diameter fuel line. Holley Sniper EFI Self-Tuning Master Kit - Black Ceramic Finish; Holley Sniper 4 Barrel Fuel Injection Conversion - Self-Tuning Master Kit + Handheld . recently purchased the 550,511k kit from holley. This fuel tank vent allows the tank to vent without spillage using a check valve. Sniper Retrofit fuel module installs in any fuel tank from 7 to 12 deep to fit a wide variety of applications, Internal fuel pressure regulator eliminates the hassle of plumbing an external fuel pressure regulator (Preset to 58.5 PSI), The low profile design is only 1.275" thick above the tank mounting surface for added clearance when needed, The innovative clamping system allows you to locate the module anywhere in the tank beside your existing sending unit, The clamping system allows you to rotate the unit 360 degrees for easier clocking of the plumbing and wiring locations under your ride, Die cast aluminum construction for corrosion resistance and long lasting good looks, NPT ports for a wide variety of plumbing options, 1965 and older U.S. manufactured California Certified vehicles, 1967 and older U.S. manufactured Federally Certified vehicles, 1967 and older Foreign manufactured vehicle, 1966 and newer U.S. manufactured California Certified vehicles, 1968 and newer U.S. manufactured Federally Certified vehicles, 1968 and newer Foreign manufactured vehicle. Today, Fuel Injection System, Holley Sniper EFI, Self-Tuning, Black Throttle Body, up to 650 HP, Kit, 4.45 out of 5 stars Ok, so if you are wondering is it worth the money, YES, will it work like they say, YES. You can order this part by Contacting Us. ( 24 ), Estimated Ship Date: How To Build A Custom Timing Table - Sniper EFI, Sniper EFI Initial Startup and Troubleshooting, How To Properly Place and Install an O2 Sensor, How to install the easy to use Sniper EFI Hyper Spark Ignition System, How To Take A Data Log From Your Sniper EFI System. Remember that each equals 1/6". Supports up to 650hp with Four 100 Lb/Hr Injectors! Simple Calibration Wizard (answer a few questions about your engine and it creates the base map, then starts tuning on its own!) Length, Kit, 4.7 out of 5 stars Put an end to cold . https://www.holley.com/products/fuel_systems/fuel_injection/sniper_efi/sniper_efi_quadrajet/ Requires external fuel pressure regulator, such as: 12-886 or 12-879, Available in base & master kits (Master kits include complete fuel system consisting of; 20ft of 3/8 Vapor Guard Fuel Hose, 12-920 Fuel Pump, Filters, necessary hardware and bulkhead fitting to return fuel into the tank! Only 4 Wiring Connections Required! (Battery +, Battery - , Switched Ignition & RPM). holley. Also in Tools, Shop Equipment & Chemicals, Cataclean - Fuel and Exhaust System Cleaner, Cataclean Diesel - Fuel and Exhaust System Cleaner, Distribution Blocks, Filters, Adapters and Fittings, Microswitch and Solenoid Mounting Brackets, Sniper EFI HyperSpark Distributor - Chevy SBC/BBC, Sniper Air Cleaner Assembly, 14" x 3" - Black Finish, Sniper EFI to Holley EFI Dual Sync Distributor Adapter Harness, Bangshift.com: The Caddy Powered C10 Gets A Holley Sniper EFI, RacingJunk.com: Installing Holley's Sniper EFI System, FullSizeBronco.com: Holley Sniper EFI Install, Compatible w/ Holley EFI, Sniper EFI, and Terminator X Software, Replacement Sniper and Terminator X O2 Sensor, Earls - 1/8" NPT in Hex if ordered today, Fuel Plumbing Kit, Tank to Regulator Location, -6 AN Diameter, 25 ft. Estimated International Ship Date: Holley Sniper 4 Barrel Fuel Injection Conversion - Self-Tuning Master Kit + Handheld EFI Monitor - Black Ceramic Finish. - NO laptop required! Not the picture of efficiency when new. Instructions are clear and easy to fallow. Holley Sniper EFI Throttle Body; For Autolite 11000 Carburetors; Gold Finish; With A Mounting Flange To Fit Autolite 1100 Carburetors Installed Throttle Body Mounted ECU No Extra Boxes To Mount Supports Up To 175 HP With One 100lb/hr Injector Only 4 Wiring Connections Required Internal Fuel Pressure Regulator Eliminates Hassle Of Plumbing Integrated Ignition Timing Control High Resolution Full . Add to Cart. I had a hard time getting them started cold and i only had a range of 75 miles and that was a big limitation. ( 2 ), Estimated Ship Date: Holley Sniper Stealth EFI 4150 EFI dual inlet fuel line with gauge. 3bar (315kPa) up to 29.4 PSI of Boost 2023 HOLLEY PERFORMANCE PRODUCTS, INC. ALL RIGHTS RESERVED. Find Holley Sniper EFI systems and intake manifolds at Summit Racing and order today for great service and fast shipping on your news parts! Unlike the former, Holley Sniper EFI will make you spend over $1000 for that combo. With the help of some youtube videos for fine tune (iac for idle), this setup works good. Included clamp-on oxygen sensor kit for 2.25" exhaust ensures a leak free oxygen sensor installation, with Stainless Steel T-Bolt clamps and a Stainless Steel (Weldable) oxygen sensor flange, Available in 3 finishes: Shiny, Black and coming soon, Gold, Bolt on 2300 Flange Carburetor Replacement, Supports up to 350HP with Two 100lb/hr Injectors, Equipped with C4 / C6 Ford transmission kickdown lever as well as TH350, 400 and 700R4 provisions, Accepts many common 5 1/8" OEM or aftermarket air cleaner assemblies, Sniper EFI Software free to download which allows for realtime tuning, Printable throttle body flange template included, Available in 3 Finishes - Classic Gold, Shiny and Black Ceramic. The Holley EFI fuel tank for C3 Corvettes (PN 19-148) and the slightly different tank for C2 Corvettes (PN 19-147) make it easy to get into EFI in a weekend. It iscriticaltousehigh pressureclamps orAN fittingstoreducethepossibilityof afuelleak. Diameter Rubber Hose, 40 ft. Also depending on the vehicle you are installing my my case a 1972 Camaro; you will also need to source a cover plate and gasket for your old mechanical fuel pump removal and also a fuel return line; these things I was aware of going into the install. Installation of the kit itself was pretty easy. Its economically priced so you can have all the benefits of EFI and still have money to finish or upgrade the rest of your ride! After I did my research, because holley kept saying the grey wire, I figured out it is the yellow wire out of the MSD 6LS box to trigger the tach iutput. From this point you will sort your fuel lines out to the fuel tank based on the chassis length and fuel pump choice (we recommend in-tank). I was able to make a fitting to put the sensor in the manifold and this and slowing the closed loop reaction down solved the issues there. Wednesday 3/8/2023 The shop did a good job, the setup is just too ugly to make look good without going out and buying extra stuff to dress and cover the wires. Add to cart. the working we wil do it after the last event The second great thng about this system is how well the self tuning works, my car started up on the first time after the install. Surprise, way smoother idle,cruise, and rediculous throttle response. I've watched the recent sniper install video from Holley and it say's the minimum fuel line size is 3/8" for supply & 5/16" for return. Bng khen, giy. By Spencer R on June 5, 2021 | Verified Owner. Part Type: Fuel Tanks. ( 50 ), Fuel Injection System, Stealth 4150 Master Kit, 4150 Flange, Polished, 870 cfm, Four 100 lbs./hr. )= HP number of cylinders x BSFC Duty Cycle. 2bar (210kPa) up to 14.7 PSI of Boost Temperature range to 450 F, so under hood temperatures will be no problem at all. There's lots of -6 fittings that have straight threads, nut, and Teflon washers. Put my sniper on a Chevy 350 and so far nothing but smooth sailing. Perfect for street rods, muscle cars, off road trucks or nearly any carbureted vehicle. The solution came in the form of a Holley Sniper EFI kitone specifically designed as a direct replacement the Rochester Quadrajet carb that our GTO, as well as countless other GM vehicles, used. View Holley Sniper EFI XFlow 1375 - Black Ceramic. $78.81. It's time to move towards better fuel economy, increased performance and perfect cold starts. Is this the right system for my vehicle, if not which one is? Includes complete fuel system consisting of; 40ft of 3/8" Vapor Guard Fuel Hose, 12-920 Fuel Pump, Filters, necessary hardware and bulkhead fitting to return fuel into the tank! i like to no before we starting the rebuld from ouder 520hp ac cobra Great product for the money car runs great after install. WARNING: It is against the law to install this part on an Emissions Controlled Vehicle, What micron is the pre filter and what micron is the post filter? I mounted a holley mech. . Stay up to date with the latest releases, events, promotions and more. Hose, Black, Straight Fittings, Kit, 3.83 out of 5 stars There is no fuel system coming with either of these two. Go EFI-4 600 HP Throttle Body System Master Kit Includes: In-line Fuel Pump (2) Holley 550-511K3 - 550-511 Sniper EFI Self-Tuning HyperSpark Kit (0) OEM Style TPS/IAC and Fuel Pressure regulator, for years of dependable service. Stay up to date with the latest releases, events, promotions and more. If you start poking around on the Holley website and notice the HOLLEY SNIPER EFI 2300 DROP-IN RETURN STYLE MASTER KIT that includes a fuel pump, you will spend an additional $73.05. The included O2 sensor is all that is needed for our Sniper TBI systems. Just wanted to share my experience and total cost for my Holley Sniper install. Started 1971 Blazer up and only adjusted AFR and runs amazing. Free Shipping over $199* Same Day Shipping before 7pm* . The following vehicles are considered Emissions Controlled Vehicles: Other self learning EFI systems require around 9 inches of vacuum - is that a requirement for the Sniper? The other hoses come in AN sizes. Designed to be a perfect fit out of the box, with no other parts or components needed. Terms of Use | Privacy and Security | Site Accessibility By Steven L on February 16, 2018 | Verified Owner. In order to get a proper estimate, we need a little more information from you. ( 1 ), Fuel Injection System, Holley Sniper EFI, Self-Tuning, Tuning Kit, Gold Throttle Body, Kit, 4.51 out of 5 stars Also in Tools, Shop Equipment & Chemicals, Cataclean - Fuel and Exhaust System Cleaner, Cataclean Diesel - Fuel and Exhaust System Cleaner, Distribution Blocks, Filters, Adapters and Fittings, Microswitch and Solenoid Mounting Brackets, Sniper EFI HyperSpark Distributor - Chevy SBC/BBC, HyperSpark Kit w/ 565-301 - Ford (260/289/302), Sniper EFI HyperSpark Distributor - Chrysler 318 / 360, Sniper EFI to Holley EFI Dual Sync Distributor Adapter Harness, Sniper EFI HyperSpark Distributor - Ford Small Block (260/289/302). The included Genuine Bosch LSU 4.9 Wideband Oxygen Sensor provides realtime Fuel Map Learn! With the sniper 550-511k kit, I have a 1980 Pontiac Trans Am with the 4.9Liter Turbo. Let's take a look at the items that would need to changed or can handle the higher pressure. Initial set up and programming was a breeze. Jul 3, 2023, Fuel Injection System, Sniper Stealth 4150, Up To 650HP, Gold Throttle Body, Four 100 lbs./hr Injectors, Kit, Fuel Injection System, Stealth, 4150 Flange, Black, up to 650 hp, 870 cfm, Four 100 lbs./hr. By browsing this website, you agree to our use of cookies. I highly recommend this setup as it has almost everything you need. My garage doesn't have the rich exhaust smell, nor the gas smell when I park my car in it.I did not use the MSD distributor features yet. Most fuel line kits feature AN fuel lines and fittings, and you can use our powerful search tools to find fuel line kits that include filters, regulators, distribution blocks, pumps, rails, and more. For starters, your fuel system will need to be upgraded. I wanted to go with an in-tank fuel pump, so got one for an EFI car and did some modifying to it for the return line. I found that the EFIPRO throttle lever extender and progressive linkage together made the sniper much more streetable. Your 7mm line is closer to 1/4", but your engine and Sniper are smaller. Not some generic pump as some have speculated. The only things you will need to source is a new throttle cable, and modify your existing bracket or purchase a FITECH GM throttle cable adapter. On to the first start. Do I need two o2 sensors sense I am running true fuel exhaust ? In lower horsepower applications a 5/16" supply line can be utilized but it is vital to take multiple pressure readings to ensure consistency. International Customer Options|In the United States? Add To Cart. Never miss a sale on new parts, tools, and more! Some parts are not legal for use in California or other states with similar regulations. Guaranteed lowest price! 2023 Holley Performance Products, Inc. All Rights Reserved. While it can move the required volume of fuel, it cannot maintain a pressure needed to supply your Sniper's fuel injectors. The 4150 manual used to say the minimum feed size is 3/8" with a 5/16" return line. Bac Giang, Vietnam. (Battery +, Battery - , Switched Ignition & RPM), Internal fuel pressure regulator eliminates the hassle of plumbing an external fuel pressure regulator (Preset to 58.5 PSI), Integrated ignition timing control & coil driver. Compatible with gasoline, race gas, and Ethanol/Methanol. Sniper Fuel Return. Got more to learn but a bad ass kit. . The included fuel pump is not compatible with E-85. ( 5 ), Fuel Tank, Steel, Silver Powdercoated, Under Bed, EFI Swap, 255 lph, 18 Gallons, Chevy, GMC Kit, Estimated USA Ship Date: Replacement TPS for Terminator and Sniper EFI Throttle Bodies as well as a variety of other Holley EFI Throttle Bodies. Hopefully, this guide will resolve some questions you may have considered when installing a Sniper EFI system. Many lower priced retrofit tanks or fuel modules have a 5/16" return tube built in. Included clamp-on oxygen sensor kit ensures a leak free oxygen sensor installation, with Stainless Steel T-Bolt clamps and a Stainless Steel (Weldable) oxygen sensor flange, 1965 and older U.S. manufactured California Certified vehicles, 1967 and older U.S. manufactured Federally Certified vehicles, 1967 and older Foreign manufactured vehicle, 1966 and newer U.S. manufactured California Certified vehicles, 1968 and newer U.S. manufactured Federally Certified vehicles, 1968 and newer Foreign manufactured vehicle. Custom fuel systems require custom plumbing solutions! Blow-through applications will require the use of an external boost referenced regulator (example: 12-848). Sniper EFI is ver. This will get you connected from the Sniper Headunit down to the frame rails. Free shipping. Ships In a Few Days. Throttle response is amazing and it made my ZZ4 come to life. Go to the below link, and scroll down to Sniper EFI Software. Brand New. ( 14 ), 4.07 out of 5 stars +84 79 555 8999. thammymimosahanoi@gmail.com. Length, Black Anodized Aluminum Fittings, Kit, 3.74 out of 5 stars Sniper Fuel Line Size. Summit Racing will BEAT any competitor's advertised price! I wish it came with fuel pressure gauge and a tune for higher altitude as I live 7000 above sea level. Opened the box and found this kit is awesome it has everything and looks great. Use our simple CFM calculator to learn what CFM you need: You should stay as close as you can to this CFM and should go no more than 50 CFM in either direction. So you're ready to switch from carburetor to fuel injection, but you're unsure of what all is involved. safely route the vapor guard fuel line along the chassis back to the diecast fuel hat, and the job is finished. So i was looking for a way to gain some range on my 33' Aquasport offshore fishing boat. ( 2 ), Fuel Line Kit, Push Lock, -6 AN Line Diameter, 25 ft. Of course you can also get Sniper kits to fit a variety of other carb/manifold types. ( 19 ), Fuel Plumbing Kit, 40 ft, Braided Stainless, With 40 Micron Filter, Check Valve, Kit, Fuel Plumbing Kit, 20 ft, Braided Stainless, With 40 Micron Filter, Check Valve, Kit, Fuel System Plumbing Kit, 20 ft., Stainless Steel, Fuel Filter, -6AN Fittings, Black, Kit, 5.0 out of 5 stars $5 Off Your $100 Mobile App Purchase - Get the App. This kit is recommended for pump or race gas use only. I have the sniper efi system with the holley retro-fit in tank electric fuel pump. I've watched the recent sniper install video from Holley and it say's the minimum fuel line size is 3/8" for supply & 5/16" for return. Holley EFI Fuel System Plumbing Kits 526-10 Fuel System Pump Plumbing Kits, Holley EFI, 3/8 in. They are engineered using Holley fuel pumps, regulators and filters coupled with quality Earl's plumbing to provide a fuel system tailored to the . If you feed something with a -6 line, and it doesn't consume all of it (like idling), then you need a -6 line for the return. If you have any issues the first question techs will ask you is whats you fuel press? New (Other) $30.00. This will be awesome! If you are seeking to utilize ignition timing control, then we recommend using one of our Holley EFI Dual Sync Distributors. Automotive Wiring: "Good Enough" Is Anything But!