There is a second limit to remove for fuelling which I don't think I've posted for 94170015 so far, so here it is...

94170015:

<table name="Set to 9 to remove fuel limit" address="265AE" type="1D" level="1" scaling="Hex16"/>

Explanation here: https://www.evolutionm.net/forums/6615273-post117.html

 

300 (2 byte) load at 29 psi@ peak load with basic bolt-on's, BC 272 cams and Meth kit. 380whp on a DJ, 330whp MD.

 

all you high load guys, what do your tables look like? I would assume you are running out of granularity since you have to spread out so much load targets in such a small table.

 

Would love to see this tested out; I know Mellon is waiting on a few parts before he can test this out. It will be a little bit before I'm able to test this myself.

 

This will need to be the next ECU mod, adding columns to the tables somehow. Thats the biggest difference between the AEM EMS and the stocker at this point.

 

jcsbanks,

I had a little bit of a hard time understanding what to do but I called Mellon and he told me I was attempting to load the new xml correctly. Works like an absolute freaking charm.

THANK YOU THANK YOU THANK YOU!!!!

 

Great David, feedback on these load caps would be good as I've done the code but not tested them. As per PM I have to go to bed, I'm on GMT+1 timezone and have to be up early.

 

I am going to give some input to what I saw and have seen over the last few weeks. I hope it helps someone out.

When I started tuning my new Project White car a few weeks ago on the stock ECU I didn't like that the fuel tables were set at say 10.5 and the AFR's were actually 11.5:1. I know from tuning the AP's that if the MAF sensor actually reads the correct flow rate the ECU will calculate the proper fueling to hit the real AFR targets that are plugged into the Fuel Tables. I wanted to accomplish this with the ECUFlash.

I was doing so many things at once that I can't remember which order I did this in but I was monitoring the MAF sensor flow and I rescaled the MAF and then I also changed the MAF Size from the stock 357.7 to 380. I chose 380 because that was the max load I was seeing and had rescaled my Fuel/Ignition talbes out to 380. Well whatever I was doing was working well because the AFR numbers in the Fuel tables were extremely close at this point to the actual AFR's I was seeing.

Shortly after all this I was pegging the 380 load and once again rescaled the load out to 420. Then last week I noticed that the 2 byte load was pegged and flat lined on the log at 403.75.

Move forward to today. I see JCSBanks post about the new addition to the xml file. I add it into my XML and it worked perfectly. The max load is now hitting 467. I spent some time on the dyno with the car tuning it and rescaled the max load out to 480 on the fuel and timing tables. The car was making great power, all pulls over 500 whp. Then I remembered I had not changed the MAF Size like I had been doing when I had rescaled the load. I then made just one changed, the MAF Size was moved up to 480. The next pull the car lost 50 whp and the 2 byte load read 513! OK, that was the clue I needed to find out why my load was so high compared to most other. I found my stock ROM, found the MAF Size was suppose to be 357.7 and entered it back into the ROM, made another pull and the power was back and then some. There was some knock now as the max load was 405'ish. I made some adjustments, rescaled the load on the fuel/timing maps to 420 and made a few more pulls. The car made the best power to date, 513 whp. MAF Size is set to 357.7 now and I'm going to leave it there atleast until I know more about how the calculation is used in the grand sceme of things.

I have a PM into JCSBanks asking that question now. If anyone else knows, feel free to chime in.

I'd like to know if there is a way to extend the MAF Scaling to let the car know that there is more air coming in. If this were possible we could all be setting the fuel tables to the actual desired AFR we wanted to run and only modifying the MAF Scaling tables to hit those targets, it works excellent doing it that way. My MAF Scaling is pegged about halfway up the scale at 255 but obviously that is not enough air flow to make the calculations work out. It IS MUCH closer though than it was with the "stock" scaling entered.

Thank you all for the help and all the work you put into this. I hope someday I am smart enough to give something back.

 

David,

AFAIK, the MAF size is something akin to injector size. I don't think it's productive to change it, as you are probably telling the ECU the MAF is a different 'size' than it actually is. I'd leave it at the factory setting. Some users rescale the MAF at the bottom of the load range (MAF Scaling table) to fix idle fueling issues, but that's a different situation.

Just so you'll know, 'Load' is basically how much air (%VE) the engine is using per revolution, and mirrors the torque curve. You should see peak load around where you see peak torque. You're probably logging either 1-byte or 2-byte load, which is what you want.

If you want to see what's happening at the MAF, log 2-byte MAF Hz (if you're using EVOScan). That gives a reading of airflow at the MAF, which basically mirrors the hp curve. When you see readings of over 3000Hz, you're really moving some air.

 

Here is the thread by jcsbanks that desribes how the ECU goes from the MAF reading to the injector pulsewidth. The Maf size looks to be a multiplier in that calculation.

From that thread, in post #1, John states:
and on the next page, in post #20, John states:
If I'm looking at the units correctly, we may infer that Maf size is actually engine size, or 1/engine size. I think I remember seeing Bez mention that before as well. Maybe John can chime in further. Perhaps the maf size should be changed slightly when changing the engine size from a 2L to a 2.3L to continue calculating accurate mass airflows.


Eric

 

wow informative thread! good stuff.

i feel terrible only hitting 280 down to 240, but i am up for a re-tune.

however, i think i have a boost leak as per my last log. 1 byte load flew up to 297 on 25psi , all i got is a TBE and 3 port on the car. i think i need to check for a boost leak!

 

As per PM to David, I would tend to leave the MAF scaling stock, or tweak it a bit along with injector size to get your fuel map to give similar to wideband AFR.

Increasing MAF scaling does increase in proportion the load that we see, but it doesn't increase the airflow that we're measuring. For that we need to delimit the two items discussed. After that, MAF scaling is just individual preference so it hits the load you want to see. Or just leave it stock and let it hit where it will.

On the speed density stuff I scale (not MAF scaling but the VE tables) to have load=MAP in kPa because like having the fuel map the same as your wideband it is tidy.

 

sounds like you're making some good headway with the load david but you mentioned 500awhp..seems low for that kind of load, I don't know your mod list though.

 

correct me if i am wrong but BR's dyno reads pretty low right?

 

it does but not THAT low, maybe David can explain, he may not be done with the tune etc...