Injector Timing? Reference Periods? refereencing what?

[S2H]

its well put together. would be nice to have the back calculated starting point in there too though. (for us lazy ones)

it is doing back calculating...you tell it valve events, it tells you where to put EOIT to match
also, if you plug your desired EOIT in the first few cells... it will spit out the EOIT represented by it to the right...but that would be the hard way to figure it out.

or were you talking about injector starting point... because its going to be dynamic depending on Injectors, and RPM

if you need a spreadsheet to calculate valve events based on duration, I can do that for you too..

[S2H]

here ya go...Cam Shaft Math for those who dont know their valve events but do know their cam specs...
I think I got it right..LOL

[Wnts2Go10O]

it is doing back calculating...you tell it valve events, it tells you where to put EOIT to match
also, if you plug your desired EOIT in the first few cells... it will spit out the EOIT represented by it to the right...but that would be the hard way to figure it out.

or were you talking about injector starting point... because its going to be dynamic depending on Injectors, and RPM

if you need a spreadsheet to calculate valve events based on duration, I can do that for you too..

back calculated injector starting point

if my idle is 875RPM and the injector pulse width at idle is ~2.5 then the starting point would be: _.

like i said, i can do the math, i was just wanting to be able to put in the numbers above and have it spit out the value i want/need. also, again, greg has said that beyond idle and lower rpm driving, the injector timing pretty much just doesnt matter because they are firing more than they arent.

[S2H]

problem is that most people are not going to be able to do the simple look and figure that out...
its going to change dynamically.. very dynamically...
Injector size, RPM, VE/MAF values, and adders for PE/OLFA... everything changes it

its not practical to back calculate starting point without using MatLab

[Wnts2Go10O]

problem is that most people are not going to be able to do the simple look and figure that out...
its going to change dynamically.. very dynamically...
Injector size, RPM, VE/MAF values, and adders for PE/OLFA... everything changes it

its not practical to back calculate starting point without using MatLab

it simply doesnt matter nearly as much the higher in rpm you go. if your idle is generally stable, it will help way more than hurt if you back calculate the starting point.

if you have the injectors set up right to begin with, that isnt an issue. especially at idle.

the VE/MAF values meter the fuel, not determine injector timing. if you argue that the pulse width increases as rpm goes up, well yes that is true, but also, more fuel is being added after the exhaust valve is closed so less is being lost in that action to begin with. so changing the timing at idle will affect low rpm drivability and power to begin with.

PE/OLFA really only matter in the higher RPM's where the injectors are firing more than they arent anyways.

[S2H]

it simply doesnt matter nearly as much the higher in rpm you go. if your idle is generally stable, it will help way more than hurt if you back calculate the starting point.

if you have the injectors set up right to begin with, that isnt an issue. especially at idle.

the VE/MAF values meter the fuel, not determine injector timing. if you argue that the pulse width increases as rpm goes up, well yes that is true, but also, more fuel is being added after the exhaust valve is closed so less is being lost in that action to begin with. so changing the timing at idle will affect low rpm drivability and power to begin with.

PE/OLFA really only matter in the higher RPM's where the injectors are firing more than they arent anyways.

The VE/MAF tables are directly responsible for telling exactly how much fuel to add...which directly equates to IPW, which equates to start time

as fuel trims change, so does your IPW

OLFA is used until you reach closed loop...which changes IPW.

EVERYTHING about our dynamic fuel system changes our injector timing..

also you every person would have to calculate differently depending on what injector they use... a 28lb injector responds way differently than a 42lb injector, and the offset tables would need to be taken int account...
trust me, I've thought about it...and not much hurts my brain... but the overwhelming data alone makes my head hurt on that one....
some things are better left up to the PCM and a computer to do the math.

find me a simple formula(that doesnt exist) and I will gladly make you a spreadsheet..LOL

[Wnts2Go10O]

The VE/MAF tables are directly responsible for telling exactly how much fuel to add...which directly equates to IPW, which equates to start time

as fuel trims change, so does your IPW

OLFA is used until you reach closed loop...which changes IPW.

EVERYTHING about our dynamic fuel system changes our injector timing..

also you every person would have to calculate differently depending on what injector they use... a 28lb injector responds way differently than a 42lb injector, and the offset tables would need to be taken int account...
trust me, I've thought about it...and not much hurts my brain... but the overwhelming data alone makes my head hurt on that one....
some things are better left up to the PCM and a computer to do the math.

find me a simple formula(that doesnt exist) and I will gladly make you a spreadsheet..LOL

check my work >.>

the starting point doesnt need to include actual ve, airflow, or any of that. if the ve is correct then the ipw is just fine to use. if the injectors are compensated for in the offset tables, ve, etc, then again, the ipw is just fine to use.

i probably should add it isnt done done but when you take into account that each .1 reference point is ~9* its easy to adjust the normal with the value.

ETA: done

[S2H]

check my work >.>

the starting point doesnt need to include actual ve, airflow, or any of that. if the ve is correct then the ipw is just fine to use. if the injectors are compensated for in the offset tables, ve, etc, then again, the ipw is just fine to use.

I have no idea what that number represents...
you have no reference to EOIT angle
example
I put in 900rpm and 3.0ms (just a value I found in an old log)
its spits out 16.2
what is that value supposed to mean?... degrees?

[SargeZ06]

I feel like Fred Sanford having a heart attack and calling out "Lizabeth I'm coming to see ya"

[Wnts2Go10O]

I have no idea what that number represents...
you have no reference to EOIT angle
example
I put in 900rpm and 3.0ms (just a value I found in an old log)
its spits out 16.2
what is that value supposed to mean?... degrees?

i labeled it wrong. it is the Injectors Degree of Duration on the 720* reference

ive refined and finished the equations

your new value should be 6.44

[S2H]

I think ISP(injector start point?) should be references to EOIT New and normal
makes more sense to think of it in degrees for me as it would equate to the exact location of the starting event...
but again.. it changes quite a bit dynamically with everything our engines do...
so just as our EOIT discussion has been so far.. take everything with a grain of salt until we can actually test

[Wnts2Go10O]

I think ISP(injector start point?) should be references to EOIT New and normal
makes more sense to think of it in degrees for me as it would equate to the exact location of the starting event...
but again.. it changes quite a bit dynamically with everything our engines do...
so just as our EOIT discussion has been so far.. take everything with a grain of salt until we can actually test

i suck at labeling(lol) and if you take actual IPW of injectors at wot or just higher rpm, it will not match up to the eoit. it actually goes outside the boundary of a 720* engine cycle

ie: 5239rpm and 10ms IPW =314* of injector duration and an eoit of 9.05 (w my cam). im wondering if i could set it up to limit it to the 9 reference points (0-8) and then recycle to really find out what it does at high rpm.

[Wnts2Go10O]

maybe it should be changed to "EOIT as calculated with ISP"?

[S2H]

maybe it should be changed to "EOIT as calculated with ISP"?

on it already...
made it show math of reference with EOIT degrees

[Wnts2Go10O]

on it already...
made it show math of reference with EOIT degrees

each tenth is ~9 degrees. i would round to the nearest .01 because of that.


could go even further to make it so the injector fires right as the overlap period begins but that might be a bit much

ETA: removed because i didnt post the new one

[LSxpwrdZ]

I like to keep the term's simple and just use 0-720* as my crank angle reference just because that tell's me which stroke I'm on. 15* ATDC can mean 2 different places in the cycle.

I can make a very simple spreadsheet to take your EOIT and your RPM and your IPW and tell you at what point in crank degrees (0-720) that the pulse will start.

[S2H]

each tenth is ~9 degrees. i would round to the nearest .01 because of that.

ETA: here, i didnt change the file name this time though

all of the EOIT values were in .01 already...
degrees in .1 because it really doesnt matter that much from 0.1 to 0.2 of a degree

[Wnts2Go10O]

all of the EOIT values were in .01 already...
degrees in .1 because it really doesnt matter that much from 0.1 to 0.2 of a degree

each .1 is 9 degrees, each .01 is .9 degrees.

[S2H]

no... the degree values... 360.1 or 360.2 (EOIT values in White cells - actual crank degrees)
.1 doesnt matter there... .1 degree translates into like 4 decimal places for Boundary/normal values

EOIT (6.41)(in Blue cells - actual value to put in the "Normal" table) was already at 2 decimals

[Wnts2Go10O]

no... the degree values... 360.1 or 360.2 (EOIT values in White cells - actual crank degrees)
.1 doesnt matter there... .1 degree translates into like 4 decimal places for Boundary/normal values

EOIT (6.41)(in Blue cells - actual value to put in the "Normal" table) was already at 2 decimals

the computer uses an 9 reference point timing system (0-8). each full point is 90* per blue cat's info. the "0" is why 9 divided by 10 is in the equation. the ls1 is based on one full cycle or 720*. if the ls1 reference was based on 360* it would be a 45* reference or half an engine cycle and would mean the equation would use 45 not 90. this is why i see the "-784" as a random number that doesnt have much to do with anything and is used only to figure out the reference point based solely on the cam.

example: with your cams True New EVC EOIT of 6.29, your injection ends by 566.1 degrees through the engines cycle.

again, this is basing it all on cats idea that the 0-8 reference table is 90* increments starting at 0 meaning 0* (the tables allow for 0.0 to 8 values).

the stock boundary is 585*
the stock EOIT is 499.5*

it does not and cannot go over 720*