values for 43 lbs and 57 lbs injectors?
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From: the not so stock tribe
values for 43 lbs and 57 lbs injectors? what numbers should be used in ls1 edit in the injector flow rate table for 43 lbs/hr injectors as well as 57 lbs/hr????
thanks in advance.
thanks in advance.
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Joined: Nov 2001
Posts: 3,048
Likes: 12
From: Raleigh, NC
Re: values for 43 lbs and 57 lbs injectors? In my discussion about my little tuning approach,
http://www.blackls1ta.com/LS1-Edit_Tuning.htm
I suggest you download this spreadsheet and play with the values.
http://www.blackls1ta.com/Tools/JohnsInjectorCalc.xls
But, be warned that either the injector offset or other conditions make the calculated values too high for my 55# injectors. Instead of an expected:
Tested Injector Flow Rate (lbs/hr) 55
Injector Test Pressure (PSI) 42.5
New Fuel Pressure to be used (PSI) 58
I ended up using:
Tested Injector Flow Rate (lbs/hr) 40
Injector Test Pressure (PSI) 42.5
New Fuel Pressure to be used (PSI) 58
I don't know if the Inj Offset is the culprit or not, but I have to go this low to make LTFT's zero/negate enough to avoid the PCM adding fuel at WOT (I only want fuel to be added at WOT based on my values placed in the PE/RPM table).
With 42# injectors, the spread was not so wide.
The bottom line is, you are going to have to put in a value that makes sense, record LTFT's and adjust IFR values down from there. Use the spreadsheet mostly for getting the correct scaling for whatever values you end up using. (If you are using an Adjustable Rate Regulator, the range of values is a flat line, and not scaled.)
http://www.blackls1ta.com/LS1-Edit_Tuning.htm
I suggest you download this spreadsheet and play with the values.
http://www.blackls1ta.com/Tools/JohnsInjectorCalc.xls
But, be warned that either the injector offset or other conditions make the calculated values too high for my 55# injectors. Instead of an expected:
Tested Injector Flow Rate (lbs/hr) 55
Injector Test Pressure (PSI) 42.5
New Fuel Pressure to be used (PSI) 58
I ended up using:
Tested Injector Flow Rate (lbs/hr) 40
Injector Test Pressure (PSI) 42.5
New Fuel Pressure to be used (PSI) 58
I don't know if the Inj Offset is the culprit or not, but I have to go this low to make LTFT's zero/negate enough to avoid the PCM adding fuel at WOT (I only want fuel to be added at WOT based on my values placed in the PE/RPM table).
With 42# injectors, the spread was not so wide.
The bottom line is, you are going to have to put in a value that makes sense, record LTFT's and adjust IFR values down from there. Use the spreadsheet mostly for getting the correct scaling for whatever values you end up using. (If you are using an Adjustable Rate Regulator, the range of values is a flat line, and not scaled.)
TECH Fanatic
Joined: Nov 2001
Posts: 1,190
Likes: 0
From: Las Cruces, NM
Re: values for 43 lbs and 57 lbs injectors? Similar experience with 50 lb msd injectors. I had to use the same flow rate as if the fuel pressure was 43 psig instead of the 61 psig (fuel pressure at the tail). Quite a bit different then it should be. I belief I have the right injector offset, so that means something is not quite right.
Gary
Gary
