How Do You Calculate Injector Flow Rate?

How do you calculate injector flow rate?

  • The formula to find the new FUEL FLOW rate after a fuel pressure change:
  • Example 1: A 240 CC injector tested at 43.5 PSI is run at 50 PSI.
  • So, the resultant change in pressure would yield the following: 240 cc/Min X 1.0721 = 257 cc/Min. 22.86 Lb/Hr X 1.0721 = 24.51 Lb/Hr.
  • What is the flow rate on my fuel injectors?

    Most injectors are flow rated at 43.5 psi. (Motorcraft rates their injectors at 39.15 psi.) If you are running a different pressure, your actual flow rate will be different than the advertised rate. For example, what happens to the output of a 24 lbs./hr.

    Can you run too big injectors?

    Bigger is not always better

    It's easy to fall into the trap of thinking that bigger fuel injectors equal more power, but unless your engine is set up to deal with the extra fuel, you'll be on a fast track to trouble. The excess fuel will flood the engine and it either won't run at all, or will be running too rich.

    How do I check my injector CC?

    you need to make a rig to apply +12V across the pins on the injector, and also have a fuel feed with pressure. once you apply the 12V, you measure how much fuel comes out in 1 minute. the volume that comes out of the injector cc's is the cc/min of the injector @ the psi of the fuel pressure.

    How many pounds are 1000cc injectors?

    1000cc (100 lbs/hr at OE 58 PSI fuel pressure) FIC Fuel Injector Clinic Injector Set for LS1 engines (High-Z)

    Related faq for How Do You Calculate Injector Flow Rate?

    What controls the fuel injector pulse?

    The (PCM) uses the trigger signal from the crankshaft position sensor; and/or camshaft position sensor to pulse the injectors.

    How do I increase the flow of my fuel injectors?

    Hold the throttle steady at 3,000 rpm and adjust the "injector size" setting higher or lower until you reach the same air/fuel ratio that you wrote down in step 3 above. Adjust the injector size lower to richen/increase fuel. Adjust the injector size higher to lean/decrease fuel.

    How much fuel pressure does a fuel injector need?

    If you want the best performance from your entire fuel system, we recommend a system pressure of 40 to 80 psi.

    How do you measure injector pulse width?

    Once you determine the base width, you then determine which factors will affect your engine performance, such as oxygen levels and coolant temperatures, and plug them into the equation "pulse width = (Base pulse)(Factor A)(Factor B)."

    What size injectors do I need for 500hp?

    Flow Rate Definition, Calculating Horsepower Range

    Injector Flow Rate Naturally Aspirated Engine Engine w/ Power Adder
    30 lbs./hr. 350-450 hp 300-375 hp
    36 lbs./hr. 425-540 hp 350-450 hp
    42 lbs./hr. 500-625 hp 410-525 hp
    46 lbs./hr. 540-690 hp 450-575 hp

    How much HP can 1000cc injectors handle?

    The 1000cc Injectors can support 650+whp.

    How much HP can 750cc injectors handle?

    Regardless of what some calculators may say, healthy 750cc injectors will easily and safely support over 800BHP all day long on gasoline.

    How do you measure injectors?

    How many cc are 65lb injectors?

    65 lb/hr (682.5cc/min) at 58 psi (Stock OEM LS operating pressure)

    What CC are 80lb injectors?

    Fuel Injectors | Siemens Deka | 80 lb/hr | 875 cc/min | High Impedance | EV1 | 6 Cyl.

    How many lb are 850cc injectors?

    850cc (94 lbs/hr at OE 58 PSI fuel pressure) FIC Fuel Injector Clinic Injector Set for LS3, LS7, LSA, L76, L92, and L99 engines (High-Z) Previously 770cc.

    What voltage should be at injectors?

    They should all be around 12 volts. A lower reading means there is excess resistance in the wire somewhere. Hopefully, these tests have allowed you to find the issue with your fuel injectors; but, as mentioned before, it may not be an electrical problem that is causing the injector to malfunction.

    What causes weak injector pulse?

    You could have bad injectors, a bad resistor box (unlikely as I haven't ever seen a bad one unless someone else has), or a wiring issue. Like stated before the ECU controls the grounds. Meaning the ground circuit for the injectors goes directly to the ecu.

    Does the ECU control the fuel injectors?

    Electronic Control Unit (ECU)

    The ECU is the brain of the operation. It uses engine RPM and signals from different sensors to meter the fuel. It does this by telling the fuel injectors when and how long to fire. The ECU often controls other functions like the fuel pump and ignition timing.

    What is injector lag?

    Injector “lag” time is the time it takes for an injector to open (OT) form the time it has been energized until it is fully open. Some engine managment systems require you to enter this time and refer to it as injector lag, latency, delay or other terms.

    Can injectors be adjusted?

    Injectors and fuel pumps for diesel engines are not something for anyone but a skilled fuel systems mechanic to try to repair. There is no way to ” clean and field adjust” an injector.

    What are injector dead times?

    The "dead time" is just the amount of time from closed to opened that a certain sized injector takes to open under a certain, voltage and fuel pressure, and to be honest is NOT THAT IMPORTANT in reality, it's one of those "fine tuning" things tht keeps a steady idle at night or when there's a load on the electrical

    Can high fuel pressure damage injectors?

    High fuel pressure results in a rich air-fuel ratio because the increase in pressure forces more fuel through the injectors than required producing increased emissions (HC's) and black sooty exhaust. These excessive hydrocarbons overheat and damage the catalytic converter.

    What is the ideal fuel pressure?

    Fuel pressure for most vehicles should stay in a 5- to 10-psi range. But, techs should make sure to look at the service information for the specifications. Other data PIDs used to regulate the fuel pump include the engine position sensors.

    What happens if fuel pressure is too low?

    Some of these symptoms include your engine running rough, poor fuel economy and black smoke from the exhaust. On the opposite side, if fuel pressure is too low, your vehicle could experience a lack of horsepower, slow staring, an inability to start the engine or stalling.

    How do you read a pulse injector?

    What is minimum injector opening time?

    Injectors are 2000cc (190 lb/hr) Bosch EV14s. The injectors are too large or the fuel pressure is too high (or both). That's why your "Minimum Injector Opening Time" of 1.5 msec is being activated.

    What is the difference between the pulse width and the duty cycle of an injector?

    The Injector Duty Cycle (IDC) is basically the percentage of time an injector is energised (open) during an engines cycle i.e. 0% IDC injector is off, and 100% IDC the injector is permanently open. The Injector Pulse Width is the time an injector is energised (open).

    How much HP can 550cc injectors handle?

    Typically, 550cc injectors are good for 350whp. You can get 350whp from 15psi from a GT30R or 10-12psi using a GT35R.

    How much HP can stock 5.3 injectors handle?

    At the low end of the 5.3 spectrum, the LM7's 25 lb fuel injectors are going to max out before they reach the 400 horsepower stage, typically around the 380 horse mark. Gen IV injectors, particularly those on flex fuel models, are at or just above the 30 lb mark, which will bring you closer to 400 horses.

    Do bigger fuel injectors increase horsepower?

    The technical answer is yes; fuel injectors can add 10 extra horsepower at peak. However, for some car owners, that minimal difference does not offset the increased cost and complexity of switching to fuel injectors or upgrading the existing stock fuel injectors.

    How much power can 1050 injectors handle?

    Stock fuel system with 1050x injectors and BAP will hit 800rwhp on E85. The key that was mentioned was a Canton filter.

    How much power can 650cc injectors handle?

    So 650cc injector= 650hp if injector is running at 100% duty cycle. I would scale it down a bit to around 80-85% duty, so that would put you at around 520-550hp range. A single walbro can flow enough fuel to feed the car about 500-550hp, but I would advise against it.

    How much HP can LSA injectors handle?

    LSA injectors are good for over 700whp NA. There are cheaper options out there. Some used LS3/7 injectors would be cheaper and plenty sufficient.

    How much HP can 800cc injectors handle?

    Based on ATS's website (, it said that the same size 800cc will give approx. 460whp. I can see how roughly 540 flywheel hp converts to roughly 460whp after transfer. For rough figuring on a 4 cylinder engine, HP is about 2/3 of injector cc.

    How much HP will 120lb injectors support?

    Rated injector flow: 120 lb/hr @ 43 PSI. Supports up to 1900 horsepower.

    How much HP does injectors add?

    Larger throttle body and injectors

    Depending on what type of engine you have, you can gain as much as 10-20 more horsepower and comparable torque.

    What is duty cycle for injectors?

    It is usually not recommended to run an injector at more than 80% duty cycle under actual driving conditions. This 80% duty cycle operating limit is taken into account to make sure the injector will be large enough to feed the engine under actual operating conditions and will not starve the engine for fuel.

    What size injectors do I need for e85?

    Registered. 500cc would be the smallest I'd recommend, and that's with much higher fuel pressure (>75psi). 650cc would be the min on a stock regulator if your motor isn't bone-stock, but anything up to 1200cc will work great.

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