Tactrix EcuFlash Info for BRZ 86 FRS Rom flash update and logging

[Kodename47]

Originally Posted by Tor

When we log "load", which load is it exactly?

Is it just MAF*60/rpm? Or is it the final load after all corrections are applied?

Also, where does "load_abs" come from?

Thanks!

I would assume that it's after all the calculations are done. Load Absolute is probably the raw MAF*60/RPM calculation. The 2 should be very similar.

[Tor]

Originally Posted by Kodename47

I would assume that it's after all the calculations are done. Load Absolute is probably the raw MAF*60/RPM calculation. The 2 should be very similar.

I wonder where e.g the 1.18 is coming from and how it's becoming 1.13. My load compensations are 0 at 2400 rpm and 0.39 at 2800. Load limit, thought probably irellevant, is 1.17. If it's some kind of smoothing, I still wonder why it smoothens it down to 1.13 if load_abs is the raw value given that it's above everywhere in that area.

Anyway comparing Base Timing B from my log vs. Base Timing B table, using "load" and rpm, it matches up within 0.1 deg taken at various rpm points.

Mainly I am interested in if it's reliable with regards to where it looks up in the tables. Getting a fair bit of FLKC where I didn't before after adjusting the engine load compensation table. But it must be due to other reasons then, since it doesn't really make a big difference in the logged load. Maybe I just got a bad tank of fuel.

[Kodename47]

Originally Posted by Tor

I wonder where e.g the 1.18 is coming from and how it's becoming 1.13.

Temperature compensations? Plus the Load looks much smoother so maybe there's some form of smoothing going on inside the ECU.

[Tor]

Originally Posted by Kodename47

Temperature compensations? Plus the Load looks much smoother so maybe there's some form of smoothing going on inside the ECU.

Temp comp was zeroed out in the tune this log was from.
http://datazap.me/u/tor/tor-224

I wonder what OFT logs as well. Looks like it would be comparable to load_abs:

[Kodename47]

My EcuTek logs look more like the smoother "Load" output. There may well be other compensations going on that we don't know/care about.

[s4nd]

Originally Posted by steve99

Thats weird i assume you changed all three di/pi tables ?

can i edit the rpm value from 5200 change to 6000 or 6500? for help adding fuel at high rpm?
thank you

Sand

[Kodename47]

Originally Posted by s4nd

can i edit the rpm value from 5200 change to 6000 or 6500? for help adding fuel at high rpm?

You can change the value but it won't add any more fuel. What are you trying to do?

[steve99]

Originally Posted by s4nd

can i edit the rpm value from 5200 change to 6000 or 6500? for help adding fuel at high rpm?
thank you

Sand

as @Kodename47 said those pi\di tables dont determine afr they just determine the amount of port and direct inection that used at any given time to achieve the required afr, afr determined by open loop or closed loop fueling tables.

Also one the rpm climbes over 5200 the ecu will just use the data in the 5200 row for any over 5200 . Ie st 6000 or 7000 if load is over
0.9 the ecu will use 20% port and 80% direct to achieve the desired afr

[s4nd]

Originally Posted by Kodename47

You can change the value but it won't add any more fuel. What are you trying to do?

Thank you,i try to change because i get lean at upper 5000 rpm,my engine is boosted. i got afr around 13 at over 5000 rpm with boost 9psi

[s4nd]

Originally Posted by steve99

as @Kodename47 said those pi\di tables dont determine afr they just determine the amount of port and direct inection that used at any given time to achieve the required afr, afr determined by open loop or closed loop fueling tables.

Also one the rpm climbes over 5200 the ecu will just use the data in the 5200 row for any over 5200 . Ie st 6000 or 7000 if load is over
0.9 the ecu will use 20% port and 80% direct to achieve the desired afr

Thank you Steve, so is it mean the bigger value at this table,the longer time to achieve target afr?

[steve99]

Originally Posted by s4nd

Thank you Steve, so is it mean the bigger value at this table,the longer time to achieve target afr?

nope nothing to do with that its just the percent of the fuel delivery that delivered by each fuel system to deliver the amount of fuel required.


0% in table means all fueling by DI injectors
20% means 20% port 80% direct
50% means 50% port 50% direct




[ame="https://www.youtube.com/watch?v=zc8aUxBZlsU"]2013 Scion FR-S | D-4S Technology Explained - YouTube[/ame]

[steve99]

Originally Posted by s4nd

Thank you,i try to change because i get lean at upper 5000 rpm,my engine is boosted. i got afr around 13 at over 5000 rpm with boost 9psi

with standard injectors your probably going to get to the limits of what the direct injection system will supply with 9 psi boost you may need to increase the port fuelling percentage to say 30% at all rpm when loads exceed 1.


If your boosted your going to also need to raise your load limits and rescale the load axis on quite a few timing and fueling tables, else that will cause lean running.


If your using MAF based fueling you may also be maxing out the maf sensor maxium maf volts is 5v.


you want to keep your DI pulse width below 7ms and port injection pulse width below 15ms


else you risk maxing out one system or the other




here's a bit of info from a pro turbo tuner mot-east tuning


"I have grown to LOVE the split DI/PI system on this car. It is more work--yes, but in practice it works incredibly well. Out of all the things we can tweak on this car to make power, the DI/PI ratios and timings are the least touched. The engineers knew what they were doing here, and any tuner who actually spent time trying out the different variations empirically, will be using something very similar to OEM.

The reality here is that DI works BEST by injecting in a very narrow window, just as @arghx7 outlined. Too early and you're blowing out the exhaust, too late and you're still injecting when the combustion event goes off. Another factor is that you don't want to inject too far away from the spark, that's why it isn't just 370 across the board.

We've seen some tuners swear by DI only, and others use 50/50 split or even full on PI in really high HP applications. I don't think either one is a good solution.

Think of it this way: DI fuel delivery will always be the optimal method, UNTIL you make the mixture too unstable or wash the cylinders. Wash is unlikely, but once you approach 7ms injection times (250+whp with e85) you begin to lose some of that benefit. The mixture becomes less stable. Between about 300whp you cross over the threshold where 35% PI has no negative effect. 20% PI on OEM tunes? We have found absolutely no repeatable HP gains, as in 0, like none-what-so-ever. Despite changes in timing, leaner or richer, more or less aggressive cam timing, or different injection timings...I think one car actually made 1hp over 20% PI mix...which is within the margin of error between runs.

So in reality, there's just no reason to overstress the DI system with long IPWs. Take advantage of the dual injection, max out the DI to about 6 ms (this way in sub freezing temperatures you have headroom) and then run port at no more than 80% duty cycle, or about 15ms.

Also, as a comparison the DI equipped FA20 in the 15 WRX...we can't run half the timing on those! DI only we hit the knock threshold at a much lower HP using DI only. Can't explain it and it's still a very new system, but it made me wish for the BRZ setup having tuned it. "

[s4nd]

Originally Posted by steve99

with standard injectors your probably going to get to the limits of what the direct injection system will supply with 9 psi boost you may need to increase the port fuelling percentage to say 30% at all rpm when loads exceed 1.


If your boosted your going to also need to raise your load limits and rescale the load axis on quite a few timing and fueling tables, else that will cause lean running.


If your using MAF based fueling you may also be maxing out the maf sensor maxium maf volts is 5v.


you want to keep your DI pulse width below 7ms and port injection pulse width below 15ms


else you risk maxing out one system or the other




here's a bit of info from a pro turbo tuner mot-east tuning


"I have grown to LOVE the split DI/PI system on this car. It is more work--yes, but in practice it works incredibly well. Out of all the things we can tweak on this car to make power, the DI/PI ratios and timings are the least touched. The engineers knew what they were doing here, and any tuner who actually spent time trying out the different variations empirically, will be using something very similar to OEM.

The reality here is that DI works BEST by injecting in a very narrow window, just as @arghx7 outlined. Too early and you're blowing out the exhaust, too late and you're still injecting when the combustion event goes off. Another factor is that you don't want to inject too far away from the spark, that's why it isn't just 370 across the board.

We've seen some tuners swear by DI only, and others use 50/50 split or even full on PI in really high HP applications. I don't think either one is a good solution.

Think of it this way: DI fuel delivery will always be the optimal method, UNTIL you make the mixture too unstable or wash the cylinders. Wash is unlikely, but once you approach 7ms injection times (250+whp with e85) you begin to lose some of that benefit. The mixture becomes less stable. Between about 300whp you cross over the threshold where 35% PI has no negative effect. 20% PI on OEM tunes? We have found absolutely no repeatable HP gains, as in 0, like none-what-so-ever. Despite changes in timing, leaner or richer, more or less aggressive cam timing, or different injection timings...I think one car actually made 1hp over 20% PI mix...which is within the margin of error between runs.

So in reality, there's just no reason to overstress the DI system with long IPWs. Take advantage of the dual injection, max out the DI to about 6 ms (this way in sub freezing temperatures you have headroom) and then run port at no more than 80% duty cycle, or about 15ms.

Also, as a comparison the DI equipped FA20 in the 15 WRX...we can't run half the timing on those! DI only we hit the knock threshold at a much lower HP using DI only. Can't explain it and it's still a very new system, but it made me wish for the BRZ setup having tuned it. "

Thank you very much Steve for the help, yes i had rescale load to 2.5g/rev both on fueling and ignition timing map, i also rescale maf sensor, and sorry, how can i increase port injector fuelling till 30% up?. what table or map should i modify?


cheers
Sand

[steve99]

Originally Posted by s4nd

Thank you very much Steve for the help, yes i had rescale load to 2.5g/rev both on fueling and ignition timing map, i also rescale maf sensor, and sorry, how can i increase port injector fuelling till 30% up?. what table or map should i modify?


cheers
Sand

to change the pi/di ratios you would need to later the three pi/di ratio tables for cold/warm/hot


I just guessed on the 30% port


you will need to look at your port and direct injector pulse widths and adjust ratio of port to direct to keep them under 7ms direct and 15 ms port.


Or possible increase size of port injectors if this cannot be done


In addition to rescaling the load axis on tables you also need to adjust the max load limits in the tune else the ecu will just truncate load at a level to low for turbo causing you to run lean.


engine load limiter A and B tables