Six_Shooter's "little" project v.240z

[Six_Shooter]

and yes you can plug on a memcal with knock filter board and wire the correct ohm knock sensor to the correct pin of the ecu and have knock control

I was sure it was possible, since it's possible to go the other way on the '7730 style ECM, I just haven't had a chance to look over any '165 schematics.

[Jayme]

I see what you are getting at... it is rather consufing in your case, as I have always just calcuated values for the injector flow rate using the % difference of stock injector vs new injector. its never sent me wrong, I only had to fudge the injector flow once and that was when the engine had a stock reg not a rising rate and later we found out the pump was shot and dropping flow at high loads.
how confident are you about your injector specs?

[Jayme]

you havent ticked single fire have you? that halves your number of pulses and you will need to double your injector rate to suit.

[antus]

From what Ive seen injector specs for Japanese engines like the L series can get hard. From looking at nissan ecus and apexi etc they tend to have dead time as a scalar and then another value as a modifier vs voltage which defines a linear slope. I guess it works well enough, but its not as accurate as what we can map. Im interested in what your doing for injectors and what you know about them. We have tried installing ford xr6 turbo injectors in to Rosses L series, and we grabbed the voltage vs injector data from OEM ford tune and that seems to work. But 550cc nissmo injectors on a VG30 are proving harder to get the low pulse width injection right, especially on a cold engine and I dont have good data. That might not be your exact concern, but Im interested in what your doing there.

[delcowizzid]

if you look at my tables 20-100kpa ends at 94 % it could be raised or lowered but im just working round some odd injectors on that car. the boost table begins at 94 and goes to 100%

[delcowizzid]

the ve tables above are actually from 2 different itinerations of the same tune boost ve 100kpa is low by 4 kpa i made those screen shots as a guide a while ago

[Holden202T]

ok Six Shooter, i understand your pain with the injector displacement calc, and everyone has their opinions, i honestly feel the best way is to go for a 100kpa peak of 85-90-100 or whatever number you prefer and tune injector rate to get that, then once you are happy with that side of it get your 100kpa (20-100kpa ve table) column and copy it across into the boost ve table, as per the tuning guide, and you should find it will be pretty close right from the beginning.

also just to show whats happening with the boost multiplier ... as VL400 said it uses this as part of the internal calc and if you really must you can change it to get more or less of a percentage change at certain boost levels. so with the standard numbers in it, i have used the values to multiply the boost VE table just so you can get a visual idea of how it is being offset (note this might not give exact results of what the ecm actually does internally)

so the below is from the tune i run on my 18psi turbo Gemini.

20-100kpa ve table

20-100kpa ve.jpg (489.68 KiB) Viewed 4255 times

then the 100kpa column from above is copied into all the columns of this table as outlined in the tuning guide.

normal boost ve.jpg (424.64 KiB) Viewed 4255 times

i have then applied the boost multipler percentages to the respective columns in red to show you what sort of results your actually getting in the delivered pulse width at the injectors.

boost ve multiplied.jpg (483.06 KiB) Viewed 4255 times

also keep in mind this table is normally flat across the kpa range, you might find like in delcowizzids case you have a increase in them, this is probably due to not having rising rate regulator, and with a rising rate regulator it might go too rich as boost increases so you might need to drop the values across the kpa range.

at the end of the day theres so many factors, cam/head efficiency, turbo flow pattern, exhaust system restrictions, fuel system capabilities etc etc that every second persons tables look and work totally different.

the end goal is to have the wideband AFR's match the commanded AFR's and everything is happy.

the below datalog is a 1/4 mile pass from the above tune, it shows in the bottom monitor how closely the target and wideband AFR's are with this setup.

2013-06-16-drags%20log1.jpg (280.63 KiB) Viewed 4255 times

the above setup is also actually with a rising rate reg, and you can see from the FPSI trace pressure drops as boost comes on, this was a fuel system on the limit of flow for methanol (need 2.3 times more of it than petrol) and from changing to E85 i have got my fuel pressure back under boost now!

i hope this might help you comprehend more how its working ?

[Six_Shooter]

you havent ticked single fire have you? that halves your number of pulses and you will need to double your injector rate to suit.

No, I haven't.

[Six_Shooter]

From what Ive seen injector specs for Japanese engines like the L series can get hard. From looking at nissan ecus and apexi etc they tend to have dead time as a scalar and then another value as a modifier vs voltage which defines a linear slope. I guess it works well enough, but its not as accurate as what we can map. Im interested in what your doing for injectors and what you know about them. We have tried installing ford xr6 turbo injectors in to Rosses L series, and we grabbed the voltage vs injector data from OEM ford tune and that seems to work. But 550cc nissmo injectors on a VG30 are proving harder to get the low pulse width injection right, especially on a cold engine and I dont have good data. That might not be your exact concern, but Im interested in what your doing there.

I'm not using Japanese injectors, they are injectors from a Ford Supercoupe. 3.8L supercharged intercooled engine. They might be the same injectors you used. I can only find similar injectors for battery voltage correction tables, that seemed to be in a good ball park with $59, but not what I say were probably correct.

[Six_Shooter]

ok Six Shooter, i understand your pain with the injector displacement calc, and everyone has their opinions, i honestly feel the best way is to go for a 100kpa peak of 85-90-100 or whatever number you prefer and tune injector rate to get that, then once you are happy with that side of it get your 100kpa (20-100kpa ve table) column and copy it across into the boost ve table, as per the tuning guide, and you should find it will be pretty close right from the beginning.

also just to show whats happening with the boost multiplier ... as VL400 said it uses this as part of the internal calc and if you really must you can change it to get more or less of a percentage change at certain boost levels. so with the standard numbers in it, i have used the values to multiply the boost VE table just so you can get a visual idea of how it is being offset (note this might not give exact results of what the ecm actually does internally)

so the below is from the tune i run on my 18psi turbo Gemini.

20-100kpa ve table

20-100kpa ve.jpg

then the 100kpa column from above is copied into all the columns of this table as outlined in the tuning guide.

normal boost ve.jpg

i have then applied the boost multipler percentages to the respective columns in red to show you what sort of results your actually getting in the delivered pulse width at the injectors.

boost ve multiplied.jpg

also keep in mind this table is normally flat across the kpa range, you might find like in delcowizzids case you have a increase in them, this is probably due to not having rising rate regulator, and with a rising rate regulator it might go too rich as boost increases so you might need to drop the values across the kpa range.

at the end of the day theres so many factors, cam/head efficiency, turbo flow pattern, exhaust system restrictions, fuel system capabilities etc etc that every second persons tables look and work totally different.

the end goal is to have the wideband AFR's match the commanded AFR's and everything is happy.

the below datalog is a 1/4 mile pass from the above tune, it shows in the bottom monitor how closely the target and wideband AFR's are with this setup.

2013-06-16-drags%20log1.jpg

the above setup is also actually with a rising rate reg, and you can see from the FPSI trace pressure drops as boost comes on, this was a fuel system on the limit of flow for methanol (need 2.3 times more of it than petrol) and from changing to E85 i have got my fuel pressure back under boost now!

i hope this might help you comprehend more how its working ?

I've done EXACTLY what you describe, get the 100 KPA numbers that I wanted, in my case I looked for 12 AFR on my WB, and without AE, though I do want to do that set up again once I get back to $12P, and give it a little more effort. I copied over those 100 KPA values to the boost table, and then started increasing the columns a little at a time to get the in boost AFR to where I wanted, once I hit 102 VE, I stopped, because I know the North American ECMs just truncate that to 100% VE, and I still wasn't getting anywhere near enough fuel. I actually didn't know about the boost AFR table until afterwards, but it was set in the 12s, and I was lucky to get near mid 13s at just 5 to 7 PSI (140 to 150 KPA) boost pressure. A few times I actually hit higher boost pressure and leaned out into the 15s. I have to control boost pressure with my throttle angle, since my base wastegate pressure is about 9 PSIG.

I understand the function of the multiplier, it's just like any other GM code, it multiplies the current VE value by the multiplier value, pretty self explanatory.

So from what you show, the boost VE table is rather useless, and could be completely eliminated, then point the multiplier at the 100 KPA value being used at that RPM, just like stock boosted code does, at least in the North American ECMs anyway, they work that way. I mean really what's the point in having a full 3D table that is the same as a 2D table, or a column of an existing table, that uses those exact same values?