100% of 440's? Didn't see that coming. I assume you have seen near stock dynos? I have seen 9.7-10 under boost from TCCS. Those cast pistons seem to be a problem. Maybe we need bigger injectors with the Lex meter if you can rewrite the timing.
3P's TCCS Disassembly/Analysis
- Thread starter 3p141592654
- Start date
I have worked out a scaled timing map to allow the Lexus AFM to be used and keep the same timing. However, there is a lot of stuff beyond timing that triggers off of the load signal, and it all gets slightly messed up.
So, I recently bought an 1UZ ECU and pulled the AFM code out of it. Turns out it uses a different calibration map than the Supra AFM. So we tried using the 1UZ cal in the Supra ECU. Dean (Grimreaper) was working out some of it before he sold his car but he was also using some Bosch EV14 injectors that were making things confusing to interpret :-(
We will sort out a good solution soon. Reynald (Rollus) is also looking at running his Supra on E85 and I just cooked up a program for him to try. There's still a lot to be learned before this is a rock solid solution.
So, I recently bought an 1UZ ECU and pulled the AFM code out of it. Turns out it uses a different calibration map than the Supra AFM. So we tried using the 1UZ cal in the Supra ECU. Dean (Grimreaper) was working out some of it before he sold his car but he was also using some Bosch EV14 injectors that were making things confusing to interpret :-(
We will sort out a good solution soon. Reynald (Rollus) is also looking at running his Supra on E85 and I just cooked up a program for him to try. There's still a lot to be learned before this is a rock solid solution.
I'm not sure what either of these comments have to do with this thread. IJZ ecu uses the same technology and has the same limitations. A 2012 mustang has a live axle. :3d_frown:
Recently I modified the base ECU software to raise fuel cut to 116% of the stock value. The reason I didn’t go higher was because my calculations showed that we would exceed 100% duty cycle above 5500 rpm, assuming VE is maintained at 116% at that rpm (5500 is where the stock auto 1-2 shift occurs). In practice, with the boost settings I have at the moment I get peak VE of about 108% at 4200 rpm, and it drops from there so it is probable that I am being too conservative.
I noticed in datalogs afterwards that even though fuel cut was gone, I still logged a peak VE of 92%, which seemed odd since I knew with the stock code I was exceeding 100% and hitting fuel cut routinely. My SBC iColor is set to .80bar,and occasionally spikes to 0.85 bar.
Did some more digging and found a table that clamps VE as a function of rpm, and above 1750 rpm that value is 92%. Weird, why does Toyota clamp VE below 100%, which means it is also clamping injector duration since injector time is linearly proportional to VE.
I went ahead and raised the clamp to 108% (8% below the new fuel cut, same ratio as stock) and did a few runs. Sure enough, VE is now peaking above 100% now, as I knew it must, and max injector times are now higher at 19ms (which is 100% duty cycle at 6315 rpm). Now Toyota adds considerable enrichment under load as we know, in this case about 35% more fuel due to the enrichment map. So even with VE clamping the enrichment will still be adding fuel as the rpm climbs.
Final thing to note is the impact of knock. You can see as soon as the throttle opened knock was detected and at peak VE over 23 degrees was being pulled for total net timing of only 15 degrees! This was a hot day and at the end of commute so everything was pretty heat soaked, still that is costing a lot of power.
I noticed in datalogs afterwards that even though fuel cut was gone, I still logged a peak VE of 92%, which seemed odd since I knew with the stock code I was exceeding 100% and hitting fuel cut routinely. My SBC iColor is set to .80bar,and occasionally spikes to 0.85 bar.
Did some more digging and found a table that clamps VE as a function of rpm, and above 1750 rpm that value is 92%. Weird, why does Toyota clamp VE below 100%, which means it is also clamping injector duration since injector time is linearly proportional to VE.
I went ahead and raised the clamp to 108% (8% below the new fuel cut, same ratio as stock) and did a few runs. Sure enough, VE is now peaking above 100% now, as I knew it must, and max injector times are now higher at 19ms (which is 100% duty cycle at 6315 rpm). Now Toyota adds considerable enrichment under load as we know, in this case about 35% more fuel due to the enrichment map. So even with VE clamping the enrichment will still be adding fuel as the rpm climbs.
Final thing to note is the impact of knock. You can see as soon as the throttle opened knock was detected and at peak VE over 23 degrees was being pulled for total net timing of only 15 degrees! This was a hot day and at the end of commute so everything was pretty heat soaked, still that is costing a lot of power.
yet another good reading Jon 
I think that VEmax=0xE800 on my code also. I will log and see results with E85.
++
Reynald
I think that VEmax=0xE800 on my code also. I will log and see results with E85.
++
Reynald
Bah ignore the 1jz comment. 1st post of his life... has nothing better to do. I just want to see the end result of your innovation
*edit* ehh guy delete his post .
*edit* ehh guy delete his post .
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3p141592654;2014570 said:
Ho OK, I just read the readme, didn't played with the shell yet. As I told in a previous mail, I will need to make 8 ignition maps with 8 injectors scaling.
What if we move to a 750cc injector? I have been also thinking of a large plastic MAF housing, (heat soak) but not necessarily the MAFT. If I did it, it surely would be draw through and not blow through.
Nick, 3p ECU allows injectors and maf scaling, so he will confirm, but it allows you to make any combination you like.
I'm not sure to catch your MAF thing..
I'm not sure to catch your MAF thing..
Yup, there is no limit, and it's easy to scale for larger injectors which takes care of the 100% duty cycle problem.
I guess my point is that with the stock 440s, fuel cut really is the end of the road. You need bigger injectors if you are hitting fuel cut, there is no software fix for it.
Scaling the AFM is tricky, because there are over 30 tables that use load as an index. Besides the big timing and enrichment tables, there are also many smaller ones that trigger off load and they all get messed up with Lex mod. But the good news is they can all be fixed.
Also, by looking at the 1UZ code we can definitively say that the Lex AFM flows 28% more air for the same frequency than the stock AFM. That makes it simple to fix things up. The real problem is that timing and enrichment tables stop at 78% load. After that the value is just held. Filling out the table at higher loads would be a good thing to do.
Getting a Turbo-A ECU would be nice, since there is a chance it has bigger maps, but that's speculation for now.
I guess my point is that with the stock 440s, fuel cut really is the end of the road. You need bigger injectors if you are hitting fuel cut, there is no software fix for it.
Scaling the AFM is tricky, because there are over 30 tables that use load as an index. Besides the big timing and enrichment tables, there are also many smaller ones that trigger off load and they all get messed up with Lex mod. But the good news is they can all be fixed.
Also, by looking at the 1UZ code we can definitively say that the Lex AFM flows 28% more air for the same frequency than the stock AFM. That makes it simple to fix things up. The real problem is that timing and enrichment tables stop at 78% load. After that the value is just held. Filling out the table at higher loads would be a good thing to do.
Getting a Turbo-A ECU would be nice, since there is a chance it has bigger maps, but that's speculation for now.
Doesn't the Turbo A Ecu is MAP and not MAF based?
I still have a friend who have "A" Option turbo/ecu, which is like having an upgraded CT-26 from factory. I will bump him to know if he will send i to Jon S. in UK to extract the code. (my former EUDM ECU is still there I think).
I still have a friend who have "A" Option turbo/ecu, which is like having an upgraded CT-26 from factory. I will bump him to know if he will send i to Jon S. in UK to extract the code. (my former EUDM ECU is still there I think).
Yes. Turbo-A is MAP based, but should have the same ignition timing and knock maps. Would be good to take a look at those.
For my friend "A" ECU above if you're interested, shoot me a mail with (Jon S. ?) adress please, I am going to organise shipping to get the code read.
Nick M;2014747 said:
I picked this number using a generic BSFC formula. It is larger than required for 500 bhp. In fact, RC's own site lists 716cc at 80%.
3p141592654;2014784 said:
So you guys are already at the point you can remap the stock ECU to various injectors?
If I were to tell you that I run 680cc's and an Lex AFM you could remap my ECU to perform correctly?
So there's a guy on the Facebook page that is running stock injectors paired with a lex afm. According to him, under normal driving afrs are 14.7-15.5, and under boost its a perfect 11.5. I don't really see any issues with this setup other than possibly maxing out injectors once TCCS adjusts the fuel maps & richens it up... Although I'm assuming that Toyota wasn't stupid when they programmed the ECU.. I'd assume that there's enough injector to hit fuel cut at max enrichment. But I just don't know.
Also, if this set up is okay, which I believe it is, then would the reworked code also work for this? Even though it's still on stock injectors?
Also, if this set up is okay, which I believe it is, then would the reworked code also work for this? Even though it's still on stock injectors?
by replacing a few ICs you can change the boost cut value. http://www.suprasonic.org/public_html/sonictech/techtom/
3p141592654;2014784 said:
What if one were to run the stock AFM would everything run good? I'm not shooting for any big horsepower, and would take the stock AFM to its limit... whatever that is.