I see people refer to this as pulse width. I'm thinking this is the amount of time the injector is open, but when I look at table B0720 the comparison of the 2 axis are mm3/Stroke per MPa value. So this is volume volume per injection event compared to, what I'm assuming to be, rail pressure value. So, my question is how is B0720 and B0721 commanding more fuel when you enter larger values? And if it is duration, the values in the cells miliseconds?

If table B0727 didn't exist, I would simply understand the longer the injector is open, the more fuel that is going to come out of it. But Throttle Based Injection Quantity (B0727) has value of mm3 of fuel/stroke per throttle position value. Wouldn't the values in those cells limit what fuel can be discharged regadless of what you enter in tables B0720 and B0721?

I'm pretty sure my logic is wrong becase I set up the McRat 20/20 tune, and the 20% increase in the B0721 and 721 tables had very noticable effects with no change at all to table B0727. I guess I'm just not getting the relationship between the Throttle Based Injection Qty table and the Main Injection Pulse table.

short answer..

TPS references mm3 in the TBIQ table.

mm3 references pulse with (uS) in the pulse width tables.

Pulse width has the last word in fueling.

I just went back and read the description on the 0727 table...not sure why that didn't make sense to me before.

Pulse width determines how the long the injector stays open. The units on this table are just used for reference after you modify it because... for example 2500 milleseconds of injector opening at 140mpa may not provide x amount of fuel or may provide more, depending on how you modified it. Understand? The axis values are still important, they just dont need to be taken for thier exact value, only as a reference.... Thats the way I see it anyways. In other words, once modified the calibration is off.... There was a thread about this not too long ago about a guys max commanded mm3 capping off at 120mm3 and he thought thats all he was getting. But really due to modifications he is getting more.

As for a relationship between the two tables your talking about. The TBIQ (throttle base injection quantity). This table works with your right foot. Whatever the throttle position is it commands a certain mm3 of fuel. That value then goes to the main injection pulse table where you have modified it so that under a certain commanded mm3 and fuel pressure you get a certain injector opening.

If you want some information on how I modified these tables send me a PM. It is fairly straight forward once you see and understand how they operate together though.

Somebody can correct me if im way off.... things are working great for me though.

The 120 was ME....IT WAS ME..... and I understand it to be a lie and Throttle based Injection Quantity doesn't matter much if the PW is anything other than stock. Otherwise it throws everything off. If that helps. In other words use the PW as the main tuning portion, and use the other for smoothing. Once you get PW figured out, the other won't matter much. You can still use the table, just don't take the values for real unless you leave the pulsewidth stock and just tune by using throttle based injection quanity.

The throttle based injection quanities in mm are off by the same percentage you multipied your pulsewidth by.

I am sure someone will correct me if I'm wrong, but that is my understanding.

for simplicity, I tend to think of the TBIQ table values as a throttle percent, rather than amount of fuel. It works for me...

:iamlost:

:iamlost:


:iamwithst

:iamwithst


:funnypost

I dunno dudes... all I know is that I like smoke. More pulse width equals more smoke. I dont know a thing about EFI, I just pretend I do and confidence is the key. You can make anyone believe you if you tell them with confidence haha.

haha, for not knowing anything i'd say we did a not bad job on our trucks with efi... but... it is very hard to explain it to others. What helped me under stand is read this whole forum once or twice over and then maybe mosy on over to EFI lives forum and maybe ready that a couple of times front to back

.


Pulse width has the last word in fueling.

it is still limited to the amount that is in the TBIQ IMO;)

:p::):p::stirthepo

:p::):p::stirthepo

who me?:D nah im just glad you boys are haveing fun with your EFI
its a great tool, and if ya think ya have it figured thats great:cool:

myself still working on a tow tune,and unsure about power:eek::D
perhaps 80 maybe a tad bit more

If the Pulse Width is high then the TBIQ will change nothing(unless you come WAY down). Now the TLIQ (BO744,743,742), that is a very different story.

If the Pulse Width is high then the TBIQ will change nothing(unless you come WAY down). Now the TLIQ (BO744,743,742), that is a very different story.


put your TBIQ at 100% throttle mark at 20 mm3 and then put it at 100mm3, then tell me it doesnt make a difference:p: if you think thats to low, then that it just showing you it does make a difference,Perhaps you just dont notice when you making the small changes

Hell,you can actually make a tune that will limp a stock trans without even touching the PW table:D

Would it be a good idea to max out the TBIQ tables before messing with the Injector PW tables?

put your TBIQ at 100% throttle mark at 20 mm3 and then put it at 100mm3, then tell me it doesnt make a difference:p: if you think thats to low, then that it just showing you it does make a difference,Perhaps you just dont notice when you making the small changes

Hell,you can actually make a tune that will limp a stock trans without even touching the PW table:DI see what you're saying Simon, but do the same you said but when you make TBIQ 20 mm3 at 100% also make the pulse at 20 mm3 the same as it is at 120 mm3. See what happens then. I think that's what was meant by pulse having the word in fueling.

Would it be a good idea to max out the TBIQ tables before messing with the Injector PW tables?



In order to stabilize your MM3 values when you are driving your truck, you need to make your throttle input steady across the board...then focus on making your torque limiting quantities and your base torque values steady....and you should have a tune that keeps the MM3 value at a constant rate based on your throttle input. If you do this right, when the truck shifts, you should see a consistent % of drop in the MM3 value while the truck defuels to shift across the RPM board. The killer part on an LLY, the MM3 drop will increase with your power at WOT once you reach a certain point...so the tune has to be adjusted accordingly. This is part of some torque reduction tables that I don't feel we have control of with EFI at this point. It is manageable with some work on the tune as the power increases, so it is not a limiting problem for power output on a LLY. It just makes a little more work when tuning one.


TIPS:

When adjusting these values leave the TBIQ,TLIQ, and BT tables alone at 0-800 rpm. These values are used to calculate fuel delivery at idle and can cause your truck to smoke at idle when the OAT drops. I leave the max fuel quantities limit tables alone at those rpm's too. The pulse tables with and without pilot should not be modified at 0-50MPa from 0-100mm3. These values are used for idling and starting your truck. Notice the very high pulse width values at the bottom of the tables? Those are used when you start your truck. If you reduce those values, your truck will start a little harder than it does stock. Keep the values from 0-800 rpm stock in the base rail psi table too. Once again...these values are used for your truck to start and idle properly. Your truck will idle at between 5mm3 and 40mm3 depending on ECT/OAT at startup and between 35Mpa and ~60Mpa depending on ECT/OAT. With this in mind, keep the values in your pulse w and w/o pilot stock at 60MPa-70MPa from 0-40mm3.

These tips are general info for those of you that don't want startup/idle issues with your stock injector trucks. Hope this helps.

I see what you're saying Simon, but do the same you said but when you make TBIQ 20 mm3 at 100% also make the pulse at 20 mm3 the same as it is at 120 mm3. See what happens then. I think that's what was meant by pulse having the word in fueling.


haha Josh that is a good point!:D:D
I love PW and realize its very important,no matter what tune i have there is some adjustments done to them

However, TBIQ is still a powerfull table and i wouldnt tune with out it either