Ultimate LT Gen V Fuel System Swap Guide

Move over LS, LT Gen V engines are the next popular Hot Rod and classic vehicle engine swap

About the GM & Chevy LT Gen V engines and upgrades made over the LS series engine

GM released the GEN V LT engine first in the 2014 Chevrolet Corvette known as the LT1 (not to be confused with the Gen 2 LT1) at 6.2L of displacement this new generation of engine generated 455HP and 460 lb.ft of torque. Not bad for a production engine!

Main LT engine upgrades over the LS series of engines

GM introduced gasoline direct injection technology on the LT Gen V engines this allows fuel to be introduced directly into the combustion chamber vs multi-port fuel injection on the LS series engines that spray fuel into the intake manifold before the valve. 

GM also upgraded the cylinder head on the Gen V LT engines with major changes being relocation of the intake and exhaust valves swapping positions and positioning the spark plug in a better location to improve combustion. All in these changes improve performance and fuel efficiency.

On the Gen V LT engines GM went all in with VVT (variable valve timing) allowing up to 62 degrees of cam timing adjustment. In theory this allows the engine to remain at peak power throughout the RPM range. 

Gen V LT engine fuel system requirements

With the change to direct port fuel injection the LT engine has different fuel system requirements than the LS Gen V series of engines. Primarily the LT engine requires a higher fuel flow and base fuel pressure than an LS engine (58PSI vs 72PSI)

PWM (pulse width modulation) or Bypass regulator and Return which to choose for an LT engine?

From the factory GM introduced a new way to control the fuel pressure on the LT Gen V engine. This being PWM or pulse width modulation control. With this type of system the ECM controls the fuel pressure by altering the voltage that is sent to the pump, this allows the pump to essentially speed up and slow down to changing fuel requirements keeping a consistent pressure to the engine and reducing pump load and extending life of the pump. In order to implement a PWM system you will require a PWM compatible pump, and integration of the fuel pressure sensor into the fuel system. 

With a bypass regulator you can control the fuel pressure mechanically and return extra fuel back to the tank with only the require pressure being provided to operate the LT Gen V engine. You will require an adjustable bypass regulator that can be set to 72PSI. 

Gen V LT engine fuel system swap required parts

Once you have decided on utilizing a pressure regulator or PWM Hot Rod fuel hose has everything you need for a successful LT engine fuel system. 

Parts list for a bypass regulator LT fuel system. 

Fuel pump selection

Up to 550 HP

Walbro 255 LPh GCA-758 Found Here (in tank pump)

Walbro  255 LPh GSL-392 Found Here (in line pump)

Up to 700 HP

Aeromotive 340 Found Here (in tank pump)

For higher horsepower applications please fill out our build request form found HERE as there may be specialized requirements and we want to make sure your fuel system is rock solid. 

 Fuel pressure regulator

Due to the higher pressure required be sure the regulator is able to support a pressure at a minimum of 71 PSI, many regulators are limited to 70PSI and while that may work it is not ideal and may not meet the requirements of your LT engine. 

Aeromotive EFI bypass fuel pressure regulator 13303 found HERE

Aeromotive A1000 bypass fuel pressure regulator 13138 found HERE

Fuel Filter

A fuel filter is required for your LT Gen V engine install with a minimum filtration rating of 10 micron (smaller number being increased filtration of smaller particles)

Factory style GM fuel filter with AN adapter fittings found HERE

Holley 10 Micron ORB - 8 inline fuel filter with replaceable element found HERE

Aeromotive 10 Micron inline fuel filter with 6 AN fittings found HERE

Hose and fitting bundle kit

Hot rod fuel hose has multiple color options for your fuel line kit that will work with the LT engine. In addition to the fuel line kit you will require 1 x 3/8 EFI quick connect to hook the system to the LT GEN V engine. You may also require a variety of adapter fittings depending on the fuel pressure regulator and filter your choose as well as the fuel pump hanger or sending unit that you need to connect to. We have a variety of adapters to complete any fuel system and if you need assistance identifying which fuel system adapters are needed on your build please fill out our build request form found HERE and we will be happy to assist. 

3/8 EFI quick connect adapter fitting to 6 AN found HERE

Hot Rod fuel hose PTFE 6 AN hose bundle kits found HERE

You will likely need 30ft to complete the LT fuel system with the pressure regulator mounted in the engine bay. If you also plan to complete your transmission cooler lines a minimum of 40ft will be needed, be sure to measure your complete system to get enough hose to finish your build. If you have additional components count out the total number of hose end fittings to complete the build. 

Extra hose end fittings can be found HERE

Our PTFE AN6 hose and fittings carry a lifetime warranty and allow you to select from a number of different fitting and hose colors. 

PWM fuel system required parts

Coming Soon