What is the maximum amount of injector opening time (mls)

[strokerjlk]

I'm way down on the learning curve here and I find this interesting but I don't see how you can have fuel control if the required duty cycle is over 100%. Doesn't make any sense to me at all. 

Maybe because the duty cycle is calculated .
And spraying on a closed valve can be a good thing .

[joe_lyons]

 So (120÷6000)×1000=20ms is the time the injector has to spray.  If the injector is open for 20ms at 6000rpm then it never shuts off and is at %100 duty cycle.   How are you adding more fuel if the injector is maxed out and has no more time to stay open?  Regardless of nitrous.  Unless the ecm is reporting an incorrect number be it the rpm or injector pulse width then there is no more time for the injector to do its job.

[Coyote]

Or more simply for me, duty cycle is calculated. OK

Duty Cycle = ms(desired) divided by ms(available at a given rpm).

So where is error possible in the calculation. The ecm knows what it wants. The ecm knows the rpm.   

I don't see how you can turn it on more time than available.  I'll sit and read.

[strokerjlk]

So (120÷6000)×1000=20ms is the time the injector has to spray.  If the injector is open for 20ms at 6000rpm then it never shuts off and is at %100 duty cycle.   How are you adding more fuel if the injector is maxed out and has no more time to stay open?  Regardless of nitrous.  Unless the ecm is reporting an incorrect number be it the rpm or injector pulse width then there is no more time for the injector to do its job.

Joe the nitrous was given as an example . And that's how I discovered that just simply adding fuel  ( Afr table ) it went to where I asked it to go . 10.5 . And it lost power and noticeably bogged the motor down .
I was at 20-22 ms with my Afr at 12.5 I was at 20-22 ms at 10.5 Afr .
I ended up at 11.3 -11.8 Afr to make best power with nitrous .
But I run 12.5 Afr for no nitrous .
All data shows injectors maxed out  5200-5500
I have tested this at the track also .
I can add fuel and kill ET and MPH

[hrdtail78]

I don't need a rifleman thought . 

I have to believe that is ripping on my service in the USMC, and something I expressed to another Marine.  Just another great example of you talking about something you know nothing about.

I wrote that in a private message to No Cents.  Asking him to leave me alone.  Like him or not.  He is my brother and I owe him duty.  Even if he betrays my trust, threatens to leave the forum once a week for attention and shares my PM's with others.  He is still my brother.  Most will not understand this, but those that do.  Understand it well.

Jim,
It's Wednesday.  Gateway is open tonight.  I was wanting to get baseline runs on my truck, but I can take my bagger instead.  Anytime I want?  I want tonight.  Put up or shut up.

[hrdtail78]

Nope the bagger is just fine

It is?  Then why did you burn up No Cents clutch because you had to borrow it.  What was going on with yours?  This is well documented over in TC section.

[joe_lyons]

So (120÷6000)×1000=20ms is the time the injector has to spray.  If the injector is open for 20ms at 6000rpm then it never shuts off and is at %100 duty cycle.   How are you adding more fuel if the injector is maxed out and has no more time to stay open?  Regardless of nitrous.  Unless the ecm is reporting an incorrect number be it the rpm or injector pulse width then there is no more time for the injector to do its job.

Joe the nitrous was given as an example . And that's how I discovered that just simply adding fuel  ( Afr table ) it went to where I asked it to go . 10.5 . And it lost power and noticeably bogged the motor down .
I was at 20-22 ms with my Afr at 12.5 I was at 20-22 ms at 10.5 Afr .
I ended up at 11.3 -11.8 Afr to make best power with nitrous .
But I run 12.5 Afr for no nitrous .
All data shows injectors maxed out  5200-5500
I have tested this at the track also .
I can add fuel and kill ET and MPH

Weird

[strokerjlk]

Nope the bagger is just fine

It is?  Then why did you burn up No Cents clutch because you had to borrow it.  What was going on with yours?  This is well documented over in TC section.

It was going to the semi finals in another class .
Semi finals is when there are 4 riders left out of 32 .

[hrdtail78]

Or more simply for me, duty cycle is calculated. OK

Duty Cycle = ms(desired) divided by ms(available at a given rpm).

So where is error possible in the calculation. The ecm knows what it wants. The ecm knows the rpm.   

I don't see how you can turn it on more time than available.  I'll sit and read.

You can't turn it on any more.  Testing injectors on the bench.  We can see the volume of fuel it can pass at a given time.  Only way to change the volume with out messing with injector is:  1.  Up the pressure of the fuel.   2. The other way is to drop the pressure on the other side of the injector.  Doing either one is raising pressure differential.

NOS does change atmosphere.  Temp and pressure are directly related.  One goes down.  The other does as well.  This still isn't control.  There is a possibility of going lean.  If you shoot for 80-85% or even 90% that leaves you enough room for a safety margin to know that you are always safe.  Just not hoping you are.  Probably why it's the rule of thumb.

[hrdtail78]

your welcome to come try your luck against it anytime you want .

Jim,
It's Wednesday.  Gateway is open tonight.  I was wanting to get baseline runs on my truck, but I can take my bagger instead.  Anytime I want?  I want tonight.  Put up or shut up.

[FLTRI]

Bob .
So If you have over 100% calculated D/C and you can still control fuel your ok ?
If you can fatten the mixture up 1-2 Afr and make the engine lose power , is that enough control?

Again, if you have 100% D/C that means the injector is basically static...open all the time. This means there is no more fuel available from the injector orifice(s).
The fact you can kill power by over driving your injectors is another indication you need bigger injectors.
Once complete injector control has been lost, power loss is expected.
Just can't get away from the physics of injectors.

"What do the terms "static" and "duty cycle" mean?
An injector in an engine turns on and off very quickly to control the amount of fuel delivered. The amount of time an injector is turned on and delivering fuel is known as the duty cycle. This is measured as a percent, so 50% duty cycle indicates that the injector is held open and held closed for an equal amount of time. When the engine needs more fuel, the time that the injector stays on (its duty cycle) increases so that more fuel can flow into the engine. If an injector stays on all the time, it is said to be static (wide open, or 100% duty cycle). Injectors should not go static in a running engine. If an injector is static in a running engine (open 100% of the time), that injector is no longer able to control fuel delivery. This could be an indication that the injector is too small for the needs of the engine. Injector duty cycle should usually not exceed 80% in a running engine at any time."

Another tidbit from injector guru"
"...A test at 100% duty cycle is used to determine the maximum amount of fuel that will flow through an injector in a given time..."

And BTW, AFAIK all sequential port EFI spray fuel on the closed intake valves...got to be that way...another physics deal.
Bob

[HD/Wrench]

I don't need a rifleman thought . 

I have to believe that is ripping on my service in the USMC, and something I expressed to another Marine.  Just another great example of you talking about something you know nothing about.

I wrote that in a private message to No Cents.  Asking him to leave me alone.  Like him or not.  He is my brother and I owe him duty.  Even if he betrays my trust, threatens to leave the forum once a week for attention and shares my PM's with others.  He is still my brother.  Most will not understand this, but those that do.  Understand it well.

Jim,
It's Wednesday.  Gateway is open tonight.  I was wanting to get baseline runs on my truck, but I can take my bagger instead.  Anytime I want?  I want tonight.  Put up or shut up.

Jim

I want you to meet Charlie. Charlie gave his life for your freedom. Our son was taken from us in 2009,.. He was in the 1318 Weapons. USMC.. I find your comment completely out of line.  I know that I have the backing of every current  & non current service personal .  You have no clue what it takes to part of the brotherhood, parent or other wise.. You seem to make many things personal here lately, I have no issue with that, How personal would you like to make this Jim? 

[turboprop]

I don't need a rifleman thought . 

I have to believe that is ripping on my service in the USMC, and something I expressed to another Marine.  Just another great example of you talking about something you know nothing about.

I wrote that in a private message to No Cents.  Asking him to leave me alone.  Like him or not.  He is my brother and I owe him duty.  Even if he betrays my trust, threatens to leave the forum once a week for attention and shares my PM's with others.  He is still my brother.  Most will not understand this, but those that do.  Understand it well.

Jim,
It's Wednesday.  Gateway is open tonight.  I was wanting to get baseline runs on my truck, but I can take my bagger instead.  Anytime I want?  I want tonight.  Put up or shut up.

Jim

I want you to meet Charlie. Charlie gave his life for your freedom. Our son was taken from us in 2009,.. He was in the 1318 Weapons. USMC.. I find your comment completely out of line.  I know that I have the backing of every current  & non current service personal .  You have no clue what it takes to part of the brotherhood, parent or other wise.. You seem to make many things personal here lately, I have no issue with that, How personal would you like to make this Jim? 

Steve - FYI '1318' is a Military Occupational Specialty (MOS), not a unit or organization. Not sure what specifically the xx18 portion means, but Occupational Field 1300 is Engineer, Facilities, Construction and Equipment (Page 3-163, MCO 1200.17E, Military Occupational Specialties Manual, Dated 08 Aug 2013). Not sure where you are getting the weapons portion from. Many parents get the details of their kids' military service mixed up. Not a big deal, my own mother has no idea what a Ranger or Green Beret is and tells people that I worked in telecommunications.

http://www.marines.mil/Portals/59/MCO%201200.17E.pdf

Thank you for your sons service and sorry for your loss.

Jason, I think I remember you or someone else saying you did your service in the aviation field, not as a rifleman ( I know, every Marine is told they are a rifleman). As a former Army guy that was glad to get air from whoever would come, I can honestly say that Marine air is the best. They always come when they say they will and dont require a five page essay to shoot danger close like the other branches do. Not sure if you flew in the 'stan or Iraq, maybe you recognize C/S Lombay 24. Anyways, thank you for your service.

For everyone else, cracking on someones service is reserved for those that have served and even then it is done with love and respect. I saw some numbers a few days ago, apparently less than 30% of adults aged 18-28 are qualified to serve in any branch of the military.

Lots of bad behavior in this thread. Everyone should just stop it and get back to talking about harleys.

RLTW/DOL

[strokerjlk]

Jim

I want you to meet Charlie. Charlie gave his life for your freedom. Our son was taken from us in 2009,.. He was in the 1318 Weapons. USMC.. I find your comment completely out of line.  I know that I have the backing of every current  & non current service personal .  You have no clue what it takes to part of the brotherhood, parent or other wise.. You seem to make many things personal here lately, I have no issue with that, How personal would you like to make this Jim? 

sorry for your loss.
you somehow taking it personal ,is your business. the comment  wasn't directed  to you or your son.
but you know that.
you can make it as personal as you want .

[strokerjlk]

Bob .
So If you have over 100% calculated D/C and you can still control fuel your ok ?
If you can fatten the mixture up 1-2 Afr and make the engine lose power , is that enough control?

Again, if you have 100% D/C that means the injector is basically static...open all the time. This means there is no more fuel available from the injector orifice(s).
The fact you can kill power by over driving your injectors is another indication you need bigger injectors.
Once complete injector control has been lost, power loss is expected.
Just can't get away from the physics of injectors.

"What do the terms "static" and "duty cycle" mean?
An injector in an engine turns on and off very quickly to control the amount of fuel delivered. The amount of time an injector is turned on and delivering fuel is known as the duty cycle. This is measured as a percent, so 50% duty cycle indicates that the injector is held open and held closed for an equal amount of time. When the engine needs more fuel, the time that the injector stays on (its duty cycle) increases so that more fuel can flow into the engine. If an injector stays on all the time, it is said to be static (wide open, or 100% duty cycle). Injectors should not go static in a running engine. If an injector is static in a running engine (open 100% of the time), that injector is no longer able to control fuel delivery. This could be an indication that the injector is too small for the needs of the engine. Injector duty cycle should usually not exceed 80% in a running engine at any time."

Another tidbit from injector guru"
"...A test at 100% duty cycle is used to determine the maximum amount of fuel that will flow through an injector in a given time..."

And BTW, AFAIK all sequential port EFI spray fuel on the closed intake valves...got to be that way...another physics deal.
Bob

Bob . I can google myself . but thanks.
I have read all the same stuff.
the thing is .. I have fuel control.
glad you did mention the physics of spraying on a closed valve

[1FSTRK]

Or more simply for me, duty cycle is calculated. OK

Duty Cycle = ms(desired) divided by ms(available at a given rpm).

So where is error possible in the calculation. The ecm knows what it wants. The ecm knows the rpm.   

I don't see how you can turn it on more time than available.  I'll sit and read.

The duty cycle is calculated from the ECM desired open time in MS. All injectors have dead time, where the injector is opening and closing, you have to subtract the dead time from the desired time to get the actual injector open time. This may not seem like much but it can be a measurable percentage and it varies with injector brand as well as actual voltage at the injector. This is why at high rpm the commanded duty cycle of over 100% will deliver more fuel.

I have seen a fair amount of testing and many of the more advanced injector companies are measuring and publishing ramp, or dead times for different brand injectors.

I do not know to what has priority in the ecm to control the injector closing, but if it opens on crank degrees and closes on time it may be possible to extend the pulse time far enough out to where the close command never happens. At this point you would add in all the dead time and gain fuel.

[1FSTRK]

Speaking of google, I just found this.
http://injector-rehab.com/shop/lag.html

The V12 Ferrari that Vic has been helping his buddy on has to have lag time programmed in for each injector.

[HD/Wrench]

prop I was upset when I typed it. ,,,,he was in 1st Battalion. 8th Marine Regiment  .

And  Jim you made it personal with all. It does not have to be directed at me.  It's not a army of 1...Hence the brotherhood part. That one comment is my issue.  Our son is still a marine and and I will not stand by and allow such behavior. Remove the comment, if you really are sorry. There was no reason to go there and it reads plain as day what the true intent was.

[hrdtail78]

Charlie was 03 something.  I was a POG, 6172.

Every Marine is a rifleman.  Telling another Marine that, if you need a rifleman is the same as calling someone brother, or semper fi.  What are we faithful to.  Each other. 

Jason, I think I remember you or someone else saying you did your service in the aviation field, not as a rifleman ( I know, every Marine is told they are a rifleman).

Every Marine is a rifleman.  I got about 12 weeks of training on my service rifle before I ever got out of boot camp.  I then had to spend 4 weeks in MCT/SOI.  At anytime I could of been stripped of MOS and turned into the basic rifleman.   Korean War history can prove this statement. 

People should not talk about what they don't know, and jimmy should just STHU and stay on the porch. 

I figured one of you guys would pop up.  I think you got the concept of faithful.  Your involved with a pretty fast fuel injected bike.  What is your take on 115% IDC?  Would like to hear your opinion on laying down a challenge.  Having your bluff called, and not showing up.  I'd bet you're a win, loose, draw show up type guy.

[turboprop]

1/8 is a very proud Marine Regiment with a proud history and an impressive combat record. Hell yea.

FYI - Steve and his wife are what is known as 'Gold Star' parents and are deserving of the utmost respect and courtesy. Military members give it, most others do not.

Love and Respect.

vr
TP

[turboprop]

Charlie was 03 something.  I was a POG, 6172.

Every Marine is a rifleman.  Telling another Marine that, if you need a rifleman is the same as calling someone brother, or semper fi.  What are we faithful to.  Each other. 

Jason, I think I remember you or someone else saying you did your service in the aviation field, not as a rifleman ( I know, every Marine is told they are a rifleman).

Every Marine is a rifleman.  I got about 12 weeks of training on my service rifle before I ever got out of boot camp.  I then had to spend 4 weeks in MCT/SOI.  At anytime I could of been stripped of MOS and turned into the basic rifleman.   Korean War history can prove this statement. 

People should not talk about what they don't know, and jimmy should just STHU and stay on the porch. 

I figured one of you guys would pop up.  I think you got the concept of faithful.  Your involved with a pretty fast fuel injected bike.  What is your take on 115% IDC?  Would like to hear your opinion on laying down a challenge.  Having your bluff called, and not showing up.  I'd bet you're a win, loose, draw show up type guy.

Hardtail, I am not getting into the tuning aspect of this as I try to stay out of these tuning 'taste great vs less filling' debates.

I will say this about that. You and Jim are both extremely passionate about FI tuning and I think this forum is a better place because both of are here and sharing your knowledge and experience. Both of you take things too far sometimes. The most intelligent people I know are also very humble.

[hrdtail78]

The duty cycle is calculated from the ECM desired open time in MS. All injectors have dead time, where the injector is opening and closing, you have to subtract the dead time from the desired time to get the actual injector open time. This may not seem like much but it can be a measurable percentage and it varies with injector brand as well as actual voltage at the injector. This is why at high rpm the commanded duty cycle of over 100% will deliver more fuel.

How will it deliver more fuel if it's static if it needs more fuel?  Dead time is taken out.  That is the limit.  Now what happens when the ECM just added fuel for temp, PE mode.......?  These are injectors.  Not nozzles.  IDC is based on the time spent closed as well.  There are problems introduced with hot injector also. 

I do not know to what has priority in the ecm to control the injector closing, but if it opens on crank degrees and closes on time it may be possible to extend the pulse time far enough out to where the close command never happens. At this point you would add in all the dead time and gain fuel.

Opening on crank degrees I can agree with.  Is that beginning, middle, or end?  I don't understand why the questioning of spraying on a closed valve?

[joe_lyons]

Now I've been taught that spraying on a closed valve at idle to 3500ish rpm is not the best idea but at a certain point its unavoidable. 

[1FSTRK]

The duty cycle is calculated from the ECM desired open time in MS. All injectors have dead time, where the injector is opening and closing, you have to subtract the dead time from the desired time to get the actual injector open time. This may not seem like much but it can be a measurable percentage and it varies with injector brand as well as actual voltage at the injector. This is why at high rpm the commanded duty cycle of over 100% will deliver more fuel.

How will it deliver more fuel if it's static if it needs more fuel?  Dead time is taken out.  That is the limit.  Now what happens when the ECM just added fuel for temp, PE mode.......?  These are injectors.  Not nozzles.  IDC is based on the time spent closed as well.  There are problems introduced with hot injector also. 

Once all the dead time is used up of coarse it can not continue to add more fuel. I was just addressing how the system could deliver more fuel to the motor at 115% calculated duty cycle than at 100% calculated duty cycle.
   

I do not know to what has priority in the ecm to control the injector closing, but if it opens on crank degrees and closes on time it may be possible to extend the pulse time far enough out to where the close command never happens. At this point you would add in all the dead time and gain fuel.

Opening on crank degrees I can agree with.  Is that beginning, middle, or end?  I don't understand why the questioning of spraying on a closed valve?

I am not making a judgement or recommendation on running injectors over 100%.
I am just giving the information as I have had it explained to me, hoping to add something more for everyone trying to get a handle on this.

[hrdtail78]

I am just asking on injector timing.  Was hopping you could tell me.