Elusive fuel
#21
Retired Mech Design Engr
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Vlad, if you are referring to the other thread, it doesn't change anything about the question of stock injectors being too small to support the HP claimed.
Dann, as we don't know the fuel system, we are using the simplifying assumption of a 1:1 manifold referenced regulator.
Dann, as we don't know the fuel system, we are using the simplifying assumption of a 1:1 manifold referenced regulator.
#22
How about we don't start a pissing match in every thread and try to discuss the topic at hand? So far your only contribution is vague/arrogant posts.
Corky is obviously attempting to justify the "other" thread with this troll thread, and I don't think its working. But I'm open for being convinced otherwise.
Why would torque, or pulsewidths, drop fuel requirements up top, when you're still flowing more air and need more fuel? Pressure =/= flow.
Maybe I should re-read his post upside-down and I'll undestand everything ()
#23
Look at Mass Air Flow. Raw meter voltage is very non linear, so a small increase in voltage at the high end is more air than it seems. Add fuel as required to maintain the desired air/fuel ratio.
Due to the decrease in volumetric efficiency as rpm increases, you get less air per cylinder cycle but more cylinder cycles per segment of time. However, looking at the plots, the volumetric efficiency does not drop off fast enough to fulfill Corky's Xmas wishes.
I think, in Corky's case we are seeing the benefits of 60psi fuel pressure and a very conservatively flow rate specification specification for the OEM injector. I have no problem maintaining 11.5/1 on OEM injectors at 7psi and ~190whp.
Computer control of internal combustion engines is easy compared to world class petrochemical plants. Our cars just lack sufficient instrumentation and computer horsepower.
Due to the decrease in volumetric efficiency as rpm increases, you get less air per cylinder cycle but more cylinder cycles per segment of time. However, looking at the plots, the volumetric efficiency does not drop off fast enough to fulfill Corky's Xmas wishes.
I think, in Corky's case we are seeing the benefits of 60psi fuel pressure and a very conservatively flow rate specification specification for the OEM injector. I have no problem maintaining 11.5/1 on OEM injectors at 7psi and ~190whp.
Computer control of internal combustion engines is easy compared to world class petrochemical plants. Our cars just lack sufficient instrumentation and computer horsepower.
#24
Look at Mass Air Flow. Raw meter voltage is very non linear, so a small increase in voltage at the high end is more air than it seems. Add fuel as required to maintain the desired air/fuel ratio.
Due to the decrease in volumetric efficiency as rpm increases, you get less air per cylinder cycle but more cylinder cycles per segment of time. However, looking at the plots, the volumetric efficiency does not drop off fast enough to fulfill Corky's Xmas wishes.
I think, in Corky's case we are seeing the benefits of 60psi fuel pressure and a very conservatively flow rate specification specification for the OEM injector. I have no problem maintaining 11.5/1 on OEM injectors at 7psi and ~190whp.
Computer control of internal combustion engines is easy compared to world class petrochemical plants. Our car just lack sufficient instrumentation and computer horsepower.
Due to the decrease in volumetric efficiency as rpm increases, you get less air per cylinder cycle but more cylinder cycles per segment of time. However, looking at the plots, the volumetric efficiency does not drop off fast enough to fulfill Corky's Xmas wishes.
I think, in Corky's case we are seeing the benefits of 60psi fuel pressure and a very conservatively flow rate specification specification for the OEM injector. I have no problem maintaining 11.5/1 on OEM injectors at 7psi and ~190whp.
Computer control of internal combustion engines is easy compared to world class petrochemical plants. Our car just lack sufficient instrumentation and computer horsepower.
Thank you.
This is, pretty much exactly where I was going.
Especially the bolded part.
#31
You dont understand VE.
You don't understand how IDC does not correlate to pulse width.
You don't understand that pulse width at a given duty cycle changes with rpm.
And you feel justified in mocking corkys understanding in these topics..
This thread is literally me answering the OP in 4 words, and 2 pages of people explaining it to you.
You don't understand how IDC does not correlate to pulse width.
You don't understand that pulse width at a given duty cycle changes with rpm.
And you feel justified in mocking corkys understanding in these topics..
This thread is literally me answering the OP in 4 words, and 2 pages of people explaining it to you.
#32
go ahead, I'm dying to hear this one.
seems like I confused the two (idc/pw) and you jumped in with the quickness to **** all over me cause you're still bitter. you stated nothing but arrogant vague bs and attempted to sound smart.
So now for the final question: do you agree with Corky's logic or no? If yes, explain, if no then we have our confirmation that you're still a bitter little b and posted for no other reason than to point out my confusion at the begining.
... ta daaa?
#35
Retired Mech Design Engr
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Exexx, we are not debating 190 HP, but 240 HP. Sure, there's headroom in the stock injectors, but 100%?
The higher fuel pressure gains sqrt(53/43) or 11% more fuel at 7psi over manifold referenced system.
My last post on this thread. Com'on guys, be civil.
The higher fuel pressure gains sqrt(53/43) or 11% more fuel at 7psi over manifold referenced system.
My last post on this thread. Com'on guys, be civil.
#40
Good grief wft is going on in this thread. I've now realized that either the automotive world has hacked up normal engineering terms to where they make no sense, or that everyone is just generally confused...
So PWM: Classically PWM is a means to control average current to something with a purely digital system. In a valve you set a fixed frequency that is much higher than the valve can physically operate and control the duty cycle of that digital signal to control the average current to the valve. This average current control allows analog control of valve position with a digital system.
WTF is going on in the car world? I see people talking about PWM being a digital signal and that the injectors actually go binary and completely turn off/on with the PWM signal? I think the MS3 is set to 60us PMW freq? I don't see a $100 mechanical valve operating at 60us...
It's like I'm at work looking at a marketing hack job of my project.
So PWM: Classically PWM is a means to control average current to something with a purely digital system. In a valve you set a fixed frequency that is much higher than the valve can physically operate and control the duty cycle of that digital signal to control the average current to the valve. This average current control allows analog control of valve position with a digital system.
WTF is going on in the car world? I see people talking about PWM being a digital signal and that the injectors actually go binary and completely turn off/on with the PWM signal? I think the MS3 is set to 60us PMW freq? I don't see a $100 mechanical valve operating at 60us...
It's like I'm at work looking at a marketing hack job of my project.