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Lean in Open Loop, need help

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Old Sep 23, 2007 | 04:37 PM
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Default Lean in Open Loop, need help

Hi
How to increase fuel in open loop,
VE It is established 100%.

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Old Sep 23, 2007 | 11:10 PM
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Increase injector size and/or fuel pressure.
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Old Sep 24, 2007 | 08:57 AM
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Originally Posted by divette
HiHow to increase fuel in open loop,VE It is established 100%.
depending on your software, using Tuner pro rt w/super 8d def., you can increase/decrease open loop afr through: 'loop open % change afr vs map or loop open % change vs temp. in Tables and Functions.
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Old Sep 24, 2007 | 09:48 AM
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What is the PW and Duty Cycle for the Injectors at WOT? You need to see if you're injectors are going static. Playing with the O/L AFR tables won't affect anything if the Injectors are maxed out.
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Old Sep 24, 2007 | 10:08 AM
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Injector Ford 30lb
Values need to be increased for downturn Afr?
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Old Sep 24, 2007 | 10:47 AM
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Originally Posted by divette
Injector Ford 30lb
Values need to be increased for downturn Afr?
Assuming you have an 8 cylinder motor with 8 30# injectors. Using the BFSC calc, 30#/hr x 8cylinders x 2 = 480hp. That's what this will support. Anything more than that, you'll need to increase size of injectors physically, or by increasing flow through higher pressures.
There's several assumptions in the calc I did above and would need to know more to make a more accurate assessment. But you can see why your AFR is probably going lean. Something tells me your producing more than 480hp.
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Old Sep 24, 2007 | 11:49 AM
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Originally Posted by mseven
depending on your software, using Tuner pro rt w/super 8d def., you can increase/decrease open loop afr through: 'loop open % change afr vs map or loop open % change vs temp. in Tables and Functions.
mseven
'loop open % change afr vs map' High numbers lower AFR and will add fuel, I correctly understand?
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Old Sep 24, 2007 | 11:55 AM
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I see you meant PE not open loop.
Dominic, if it is a bigger inch motor, don't you think that cylinder volume can play a role here?
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Old Sep 24, 2007 | 02:56 PM
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Not, Above on a picture with tables. I speak about them
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Old Sep 24, 2007 | 09:04 PM
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ok, the dyno chart mislead me
Originally Posted by divette
mseven
'loop open % change afr vs map' High numbers lower AFR and will add fuel, I correctly understand?
correct, the higher the positive values=lower afr (yes, richer)
increasing fuel through injecter constant/s works as an inverted table, a lower number here will increase fuel, higher number will reduce. I agree w/Dominic in knowing PW and duty cycle numbers. The other thought I had would be using PW factor vs temp or PW factor vs MAP, however if it is maxed and going static then this would be of no help.
I am guessing you are doing open loop tuning here (based on lower ve #'s, upper ve looks maxed out )? It might just become more practical to use a bigger injecter.

Last edited by mseven; Sep 24, 2007 at 09:21 PM.
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