been working on setting up one of my cars for E85 now and ran into a few hang up's. the major one was no matter what i did to get the 30-40% more fuel into the engine from the 93 pump gas map for the car i used as a base my load value was completely out of whack. using the injector constant at 3bar with it set to 1600cc because thats what my injectors are and using the dead time chart that was provided with my injectors when bought was not working at all. i decided to try and understand better how the injector control worked and honestly all this is in the M232 wiki that PRJ has provided for us. after looking all that over again the only logical thing to do was to not use my actual injector size in the constant or my actual dead time table. than i got curious about how the base injector multiplier in VEMS is calculated so i went and looked. as a test i made a scalar in tuner pro based on this that would show the injector constant value in MS instead of the actual injector size. i calculated the time in MS using the equation from the VEMS help menu than added 40% to that value and and loaded that BIN to my car and it worked perfectly! a little too much fuel actually but i could than pull back the VE_MULTIPLIER and VE_ADDEND to remove fuel from and lean out the AFR mixture because i was off the gauge below 10.0AFR and doing so put my load right around 18-19 with all the right fuel. i also had to bump around the injector dead time table a little bit as well to find the sweet spot but calculating the injector constant in MS definitely worked for me.
Heres what you need to make a new constant thats in ms.
HEX address = 0x8399
equation = X*0.0500
decimal places = 2
The equation from VEMS is as follows.
-Inj time MS = 6.49 * (D / N / I)
D: engine displacement (cc) = 2226cc unless you have a stroker
N: number of primary injectors = 5
I: injector flowrate (cc/min) = whatever your injector size is in CC.
-This formula applies to gasoline, this value needs to be increased to run with fuels that have lower air fuel ratios. Typically 30-40% higher with E85, and more than double with methanol.
so in the case of my car the equation works like this.
1.8058425 MS=6.49 * (2226 / 5 / 1600)
Than i used the simple online calculator below to add 40% to 1.8058425 to get the end result of 2.5281795 MS.
http://www.percentagecalculator.co/A...ercentage.html
im sure if this keeps working out positively for me i will make a convinence function similar to the one PRJ made for the MAP sensor scalars and pressure offsets easy to cope with. do something like put your injector size into a scalar and it does the math to calculate the time in MS for the actual constant than a second constant that will take the value in MS in your injector constant and add X % to it if running anything else other than pump gas. hope this is useful to someone and PRJ has input on it.
Heres what you need to make a new constant thats in ms.
HEX address = 0x8399
equation = X*0.0500
decimal places = 2
The equation from VEMS is as follows.
-Inj time MS = 6.49 * (D / N / I)
D: engine displacement (cc) = 2226cc unless you have a stroker
N: number of primary injectors = 5
I: injector flowrate (cc/min) = whatever your injector size is in CC.
-This formula applies to gasoline, this value needs to be increased to run with fuels that have lower air fuel ratios. Typically 30-40% higher with E85, and more than double with methanol.
so in the case of my car the equation works like this.
1.8058425 MS=6.49 * (2226 / 5 / 1600)
Than i used the simple online calculator below to add 40% to 1.8058425 to get the end result of 2.5281795 MS.
http://www.percentagecalculator.co/A...ercentage.html
im sure if this keeps working out positively for me i will make a convinence function similar to the one PRJ made for the MAP sensor scalars and pressure offsets easy to cope with. do something like put your injector size into a scalar and it does the math to calculate the time in MS for the actual constant than a second constant that will take the value in MS in your injector constant and add X % to it if running anything else other than pump gas. hope this is useful to someone and PRJ has input on it.
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