Understanding the lt direct injection fuel system for swapping – hot rod network
To make this happen, GM chose to utilize a secondary fuel system controller. Pulse width modulation pdf The fuel computer drives the fuel pump through pulse width modulation (PWM), and monitors the pressure with a sensor. Pulse width modulation ppt We chose to make our own sensor mount using a piece of fuel aluminum fuel rail (this is a Holley rail). Pulse width modulation lab manual First, the center of the rail was drilled at approximately 85 degrees-perpendicular to the fuel flow.
What is pulse width modulation The ends were already tapped for -6 fuel line. How does pulse width modulation work Next, the block was tapped with a 9/16-18 tap to match the -6 AN adapter we are using for the sensor. Pulse width modulation circuit using 555 timer The sensor rail was then assembled with an Aeromotive post filter (after the sensor), the sensor and a -6 to 10mm O-ring adapter.
Instead of a basic fuel pump and regulator, the factory supply pump is controlled by the ECM through a fuel pump module to control the base fuel pressure as it reaches the mechanical DI fuel pump. Pulse width modulation using 555 timer ic A special pressure sensor in the fuel line monitors the pressure of the fuel, which is maintained at 72 PSI at 45 GPH. Pulse width modulation 555 Rather than use a regulator, the pressure is managed through Pulse Width Modulation or “PWM” control of the pump. Sine triangle pulse width modulation Essentially, the ECM switches the voltage and current sent to the pump on and off at a very fast rate to control the speed of the pump, ensuring full pressure at all times with no delays. Pulse width modulation theory pdf With a typical electric fuel pump, when you romp on the throttle, there is quick surge in fuel flow followed by a lull as the pump recovers from the sudden loss in pressure. Pulse width modulation led dimming If plumbed properly, a port-injected engine won’t see too much performance drop from this scenario. Pulse width modulation nptel In a DI engine, this would cause a serious issue as the mechanical pump needs full pressure at all times to maintain the 2,000-plus PSI needed to correctly operate. Types of pulse width modulation techniques This complicates the fuel system for the LT-series engine swap. Pulse width modulation using ic 555 You can’t use just any old fuel pump. What is pulse width modulation pwm DI fuel pumps have to be PWM capable, and not all electric fuel pumps are.
Another factor is that the LT fuel system is returnless; this was done to keep the fuel temperature down. Pulse width modulation labview Because hot fuel does not cycle through the pump, to the engine, and back to the tank, the fuel temp remains even. Theory of pulse width modulation and demodulation Returnless fuel pumps are rarely suitable for EFI use without PWM control, and the ones that are available cannot support the type of pressure and flow needed for an LT. Pulse width modulation circuit pdf The pump requirements are 72 PSI at 45 GPH (Gallons Per Hour) and an 84 PSI pressure relief to be compatible with the Chevrolet Performance control system, which is a pretty high burden for a street-driven electric fuel pump. Carrier based pulse width modulation So where does that leave us for LT swaps?
We mounted the assembly to the hardline under the car. Pulse width modulation waveform The fuel line requirements are 3/8 or -6. Pulse width modulation for power converters principles and practice download A braided high-pressure rubber line was used to connect the filter to the engine. Use of pulse width modulation The fuel computer was mounted to the top of the transmission crossmember. Explain pulse width modulation The box is weather-tight, but the connections should be positioned so that water does not collect and stand in the connector. Pulse width modulation and demodulation theory Up top, we used a push-on adapter to connect the -6 flexible fuel line to the fuel rail. Pulse width modulation circuit 555 For the actual pump, we opted for an Aeromotive Phantom 340 in-tank pump kit. Digital pulse width modulation This system is capable of handling the pressure and flow demands, and can be configured for returnless operation with the PWM control. How to generate pulse width modulation In order for the Phantom 340 to work without a return line, this plug must be drilled with a 1/32” drill bit.
There are two options for retrofitting LT DI-compatible fuel systems: a PWM control system or pump/regulator/return line system. Pulse width modulation with 555 timer Many swappers already have an existing electronic fuel system in their vehicle. Pulse width modulation generation Swapping an LT into that scenario could mean buying new parts, but all is not lost. Ne555 pulse width modulation It is possible to bypass the PWM-style pump system by using a standard electric pump with a return line and regulator set to 72 PSI at 45 GPH. Pulse width modulation circuit for dc motor control That is fairly high for a continuous-use street pump, so make sure your pump is capable of providing the required flow and pressure. Pulse width modulation arduino The duty cycle of that pressure and flow rate will certainly be high and the lifespan of the pump will be quite low. Pulse width modulation in microcontroller 72 PSI is high for a street fuel system, and so is the flow rate of 45 GPH. Pulse width modulation theory A typical retro-fit EFI inline fuel pump can flow 42-45 GPH, but only at 15 PSI. 555 timer pulse width modulation This means you need a much larger fuel pump to supply the engine with enough fuel to operate. Pulse width modulation inverter ppt You will suffer from hard starting along with drivability and hot fuel issues. What is meant by pulse width modulation Switching to the PWM system gives you greater control.
Installing the PWM controller is simple plug-and-play, but the fuel pressure sensor and fuel pump wiring is a bit tricky. Pulse width modulation controller kit First, you need an inline adapter with a pressure sensor port positioned between 5- and 85-degrees to the horizontal flow of fuel, according to the GM manual for the fuel controller. Pulse width modulation nedir This is fairly easy, as there are plenty of these fuel sensor adapters out there. Pulse width modulation wiki The problem is that most of the adapters are for 1/8” npt fittings, and not the 10mm threads required for the GM sensor. Pulse width modulation example Finding a 1/8” npt male to 10mm male adapter is difficult. 555 pulse width modulation circuit At this point, there is no commercially available sensor adapter for the LT-series pressure sensor. Pulse width modulation ac motor speed control What you can find easily is a -6 AN male to 10mm adapter. Pulse width modulation pic To use this, you need an aluminum fuel log or Y-block fuel splitter and a -6 to 10mm male-male adapter. Pulse width modulation disadvantages This allows you to connect the sensor into the fuel system. Pulse width modulation generator We made one with a leftover piece of fuel rail from another project. Pulse width modulation using 555 timer circuit diagram The pump assembly is then dropped into the tank and bolted down as directed. Pulse width modulation for power converters principles and practice pdf Because the pump is now returnless, the return port on the mount should be blocked with a plug. Pulse width modulation vfd All of the fittings are -6 AN. Definition of pulse width modulation Coming off of the fuel computer harness are these three wires, which connect to the fuel pump. Pulse width modulation fan The color codes are as follows: yellow w/ black- pump ground, gray- pump positive, small black- shield (do not ground). Pulse width modulation animation We stripped the wires so that they could be extended. Pulse width modulation tutorial The new extension wires can be whatever colors you choose. Pulse width modulation basics The three wires were loosely braided together for optimum shielding. Pulse width modulation radiator fan controller Here you can see how the wires were laid out. Pulse width modulation experiment We opted for red w/ black stripe- pump positive, black w\ white stripe- pump ground, and small black for shield. Pulse width modulation matlab Splicing these wires requires soldering to ensure good connections with minimal resistance. Pulse width modulation led driver A good soldering job is critical for good conductivity. Pulse width modulation dc motor Always heat the wire from below and add the solder from the top, so that the solder flows through the wire. Advantages of sinusoidal pulse width modulation This will help eliminate cold solder joints. Pulse width modulation duty cycle Each splice gets heat shrink as well. Pulse width modulation using 555 Finally, the new wires are wrapped with Painless Performance Classic Braid for protection from the elements. Pulse width modulation synth Each of the new control wires get a ring terminal on the power and ground feeds, while the shield wire is taped to the other two wires as close to the terminations as possible.
Wiring the pump itself takes a little patience. Pulse width modulator hho There are three wires coming off the pump module, yellow with a black stripe, gray, and a smaller gauge black wire. Pulse width modulation and demodulation Unlike a typical installation, the power wires are only 14 gauge. Uses of pulse width modulation PWM control also eliminates the need for power relays. Pulse width modulation valve The yellow/black wire is the ground, the gray wire is the power side, and the small black wire is the shield. Pulse width modulation vape If you are using a GM pump with a shield pin (such as a 2014 Corvette or truck), connect the small black wire to that pin, if you are using a pump without a shield pin, leave the wire un-terminated and tape it to the other wires. Sinusoidal pulse width modulation for 3 phase inverter Because of the nature of PWM control, there is a very real potential for EMI (Electro Magnetic Interference) from other electronics in the car. Application of pulse width modulation To eliminate this from interrupting the control signal, the two main power control wires are twisted with a 3 rd shielding wire. Pulse width modulation microcontroller The Chevrolet Performance wiring harness only comes with a short length of wire; most cars require longer wires. Sine pulse width modulation To maintain the shielding, you have to twist the wires at a minimum of 27 twists per 8 foot of wire. Disadvantages of pulse width modulation The best way to ensure that the wires are correctly twisted and won’t unravel is a braid. Pulse width modulation 555 timer Braid the three wires together in a loose, consistent manner, it does not need to be a tight braid, wrapping the wires around each other every 2 inches or so. Pulse width modulation and demodulation theory pdf Do not use crimp connectors for these wires, make sure you solder them well and use shrink tubing.
For our install, we used an Aeromotive Phantom 340 in-tank pump kit, wired to the Chevrolet Performance ECM and fuel control module in a 1971 Buick GS with a new 6.2-liter LT1 crate engine. Pulse width modulation heater control The fuel pump was installed into the factory fuel tank, and wired directly to the GM fuel control module. Pulse width modulation circuit design The wires were extended roughly 10 feet and wrapped with Painless Performance Classic Braid.