Lowest acceptable fuel pressure for fuel injector?
#1
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Just as the title states, what is the lowest fuel pressure you can run on an injector before it gets an erratic spray pattern at atmospheric pressure?
I am running 03-04 cobra injectors on an L33, so I was thinking about running a lower pressure to help with idle tuning and such, plus its easier on the fuel pump (and will flow more at the lower PSI).
Thanks!
I am running 03-04 cobra injectors on an L33, so I was thinking about running a lower pressure to help with idle tuning and such, plus its easier on the fuel pump (and will flow more at the lower PSI).
Thanks!
#3
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Those injectors are not made for our engines. The have a 30* cone pattern that washes the front and rear walls of the intake port instead of hitting the back of the intake valve.
Changing fuel pressure is not the right way to tune. Get the right injectors, put the correct injector data for those injectors in your tuning software and tune it.
Call Jon at FIC fuelinjectorconnection.com He will take care of you.
Changing fuel pressure is not the right way to tune. Get the right injectors, put the correct injector data for those injectors in your tuning software and tune it.
Call Jon at FIC fuelinjectorconnection.com He will take care of you.
#4
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Changing fuel pressure is not the right way to tune. Get the right injectors, put the correct injector data for those injectors in your tuning software and tune it.
Call Jon at FIC fuelinjectorconnection.com He will take care of you.
one thing you have to watch mike, is the intake tract has pulses from the firing of the engine. you have to make sure you have enough fuel pressure for the spray pattern to overcome thoes pulses and still spray like its supposed to. think about it like this, pissing into the wind, if you dont **** hard enough it will come back and soak you. lol
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Well, last I looked the Fords were still 3-bar so 40PSI
ought to be "no surprises".
Question is, how well the "fuel model" matches the fuel
shot reality - PCM has a pretty lame idea of what true
pressure is, unless you have a manifold referenced
regulator close-in.
ought to be "no surprises".
Question is, how well the "fuel model" matches the fuel
shot reality - PCM has a pretty lame idea of what true
pressure is, unless you have a manifold referenced
regulator close-in.
#7
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It is a vacuum operated fuel pressure regulator sitting about 12 inches from the back of the intake manifold. The injectors are freshly cleaned 03-04's being suppied by an aftermarket rail, Aeroquip AN-6 feed, and a Walbro 255 high pressure pump..... Its ready for anything I want to throw at it, but right now I'm only going to be throwing 350-370rwhp which STOCK injectors can still handle, let alone an injector that flows 47 lb's at the stock 60psi.
BWW3588- Yea, I've pissed into the wind enough on this project...... No need to do that anymore!
BWW3588- Yea, I've pissed into the wind enough on this project...... No need to do that anymore!
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#8
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You are not going to overcome an incorrect spray pattern by backing down the fuel pressure. You will just get more un-atomized fuel in the wrong location.
I speak from experience, I ran those when I first built my current setup. Ran OK but was somewhat inconsistent tuning. I took the intake off to look at a knock sensor and saw that the front and rear walls of the intake ports were spotless, the injector angle was so wide that it washed the ports which in turn will cause the fuel to puddle on the valve, that leads to inconsistent fueling.
There are much better injectors to choose from, you can easily sell the SVO ones and just get some LS1 injectors that are sized correctly, have the correct pattern, and the injector data is already on the PCM so tuning is easier. But what do I know.
I speak from experience, I ran those when I first built my current setup. Ran OK but was somewhat inconsistent tuning. I took the intake off to look at a knock sensor and saw that the front and rear walls of the intake ports were spotless, the injector angle was so wide that it washed the ports which in turn will cause the fuel to puddle on the valve, that leads to inconsistent fueling.
There are much better injectors to choose from, you can easily sell the SVO ones and just get some LS1 injectors that are sized correctly, have the correct pattern, and the injector data is already on the PCM so tuning is easier. But what do I know.