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sean's cheap thrills, 90 1.6 with subaru td04

Old May 11, 2016 | 10:58 AM
  #1321  
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You will not max out the injectors on pump gas.
And the 90 idc number in TS is more like 60-65 realistically.
Old May 11, 2016 | 10:59 AM
  #1322  
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Also, duty cycle over 100% does not mean more fuel.

It means you were trying to inject more fuel. But it can't happen.
Old May 11, 2016 | 11:00 AM
  #1323  
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Originally Posted by 18psi
And the 90 idc number in TS is more like 60-65 realistically.
Not according to james.

Megasquirt Support Forum (MSEXTRA) ? Could maxed out injectors cause this? (View topic)
Old May 11, 2016 | 11:06 AM
  #1324  
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I will take Aidan's guess minus 1. Someone else take his guess +1. See what I did there.
Old May 11, 2016 | 11:16 AM
  #1325  
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Originally Posted by aidandj
Also, duty cycle over 100% does not mean more fuel.

It means you were trying to inject more fuel. But it can't happen.
I have tested it. And it's not right. According to me.

IN REAL LIFE BRO.
you want to see that screen shot again? I kept adding until it couldn't. they were well past 100 and still adding more fuel
many other ecu's do the same thing. I think its like a safety/cushion zone. so I don't see the need to cap it for no reason

But please, tell me more about how injectors work. I no haz idear breh
Old May 11, 2016 | 11:20 AM
  #1326  
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Its simple. 100% means that the injector is open all the time. Any more doesn't open it more.

Go open your faucet 100%. Then open it another 20%. Did you get more water?

James is the one that wrote the code. Which controls the injector.
Old May 11, 2016 | 11:23 AM
  #1327  
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Originally Posted by aidandj
Its simple. 100% means that the injector is open all the time. Any more doesn't open it more.

Go open your faucet 100%. Then open it another 20%. Did you get more water?

James is the one that wrote the code. Which controls the injector.
are you dense or just having a Leafy day?
you're talking theory, I'm talking reality.
What happens when TS is telling you its at 100 but you increase ve cells and it keeps adding fuel?
either you weren't at 100, or your injector settings are off. except it does this on multiple injectors, using "known" settings that everyone uses.
Old May 11, 2016 | 11:24 AM
  #1328  
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Need me to link more sources?
Old May 11, 2016 | 11:24 AM
  #1329  
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Megasquirt Support Forum (MSEXTRA) ? Why Is My Injector Duty Cycle % So High? (View topic)

Megasquirt Support Forum (MSEXTRA) ? Duty cycle up to 93% (View topic)
Old May 11, 2016 | 11:26 AM
  #1330  
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Originally Posted by 18psi
plots?
He's going to the dyno to get tuned, either it makes the power or it doesn't. Can't really involve more plot than that.
Old May 11, 2016 | 11:27 AM
  #1331  
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Is actual fuel delivery vs. duty cycle linear? I'd think probably not?
Old May 11, 2016 | 11:28 AM
  #1332  
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Originally Posted by aidandj
Need me to link more sources?
no.

answer my question


I know an injector can't open past 100%
that's not the discussion here
Old May 11, 2016 | 11:29 AM
  #1333  
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Duty cycle is calculated from PW. The megasquirt calculates that you need more PW than can fit in a cycle. So your injector is open 100% of the time from 100% up to 255% (the max that the megasquirt can return, because calc_duty returns an unsigned char, which has a max of 255)
Old May 11, 2016 | 11:30 AM
  #1334  
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I'm not talking theory. I'm talking reality. As in what the actual code inside the microcontroller does.

This isn't some silly theory, this is what happens in the code.
Old May 11, 2016 | 11:33 AM
  #1335  
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Here is a good one from Matt Cramer

Originally Posted by Matt Cramer
If 1 squirt simultaneous works, it works, no reason to change it.

It appears your injectors are sized in such a way that they deliver just enough fuel to the engine at full throttle when they go static, and the VE table is actually higher than it needs to be. I'd advise larger injectors or a bump in fuel pressure to give you some reserve capacity.
Your injector goes static at 100%. It probably just delivers enough fuel to keep it running at an acceptable AFR range when going full throttle.
Old May 11, 2016 | 11:33 AM
  #1336  
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Originally Posted by aidandj
I'm not talking theory. I'm talking reality. As in what the actual code inside the microcontroller does.

This isn't some silly theory, this is what happens in the code.
reality is what we observe and document from testing.

so the question then is, if 100% really equals 100%, why then can I actually increase and decrease fueling past the reported 100%

do you seriously not understand what I'm saying?

Originally Posted by aidandj


Your injector goes static at 100%. It probably just delivers enough fuel to keep it running at an acceptable AFR range when going full throttle.
I would agree except I was able to accurately control fuel, not just have it peg at an acceptable afr.
Old May 11, 2016 | 11:34 AM
  #1337  
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Because you aren't actually increasing and decreasing fueling.

At 100% DC your injector is static.
Old May 11, 2016 | 11:36 AM
  #1338  
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Originally Posted by aidandj
Because you aren't actually increasing and decreasing fueling.

At 100% DC your injector is static.
I just told you that I am.

dude........seriously

I'll replicate this on the next one I do if I don't forget.

if it's static then you shouldn't be able to increase fuel. its stuck open, it will deliver what it will deliver. you have no control of fueling at that point.
Old May 11, 2016 | 11:37 AM
  #1339  
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Dude...seriously.

I'll scope an injector tonight at 100% DC.
Old May 11, 2016 | 11:39 AM
  #1340  
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Originally Posted by aidandj
Dude...seriously.

I'll scope an injector tonight at 100% DC.
holy crap, you are retarded today. like, just simply does not compute

nevermind

*edit: maybe we're all just using incorrect injectors settings. all of us. on all of our cars.

there. that would validate everything you're saying

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