I am still tuning my Northstar bin on my 7730 ECM using TunerPro.
The XDF, original bin file, and adapted ECM were are developed by Ryan Hess.
The bin Ryan wrote was intended for the Vin 9 engine, so anyone running a Vin Y engine will be running quite rich, myself included.
So the need to tune the fuel maps, the acceleration enrichment, and the power enrichment fueling.
Some dyno time and a wide band O2 input has been very helpful to confirm this.

But here's the rub:
Before going beyond low load and idle tuning the fuel charts need to be fully understood.
There are 2 VE charts for fuel control: Idle and Main
The Idle VE chart goes from 600 to 1600 rpm and the Main VE chart goes from 600 to 4000 rpm, both for MAP of 20 to 100Kpa.
There is also a VE adder vrs RPM chart that goes from 0 to 6500 rpm and adds 25 to 50% VE
What determines what VE chart is used since they overlap?
What VE is used above 4000 rpm and how is it changed? Is the VE adder used somehow here?
When PE mode is entered, what defines the VE or is the AFR determined by the "PE Mode AFR vrs RPM" chart?

Reading the ThirdGen site has been an incredible help for me, but the Northstar program just have some differences from the SBC stuff the 7730 usually runs, unless I am just not seeing it.
The ThirdGen tuning links are:
http://www.thirdgen.org/tec...ning-guide-book.html
and
http://www.diy-efi.org/gmec...ers/tunetip.html#maf

Anybody else have much knowledge/experience with tuning Ryan's Northstar 7730 program with TunerPro?

Once I get this figured all out, I intend to consolidate all the info I have learned/gathered up from the different posts I have made about tuning my Northstar.

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Daviero - 88 N* GT

quote Originally posted by Daviero: There are 2 VE charts for fuel control: Idle and Main What determines what VE chart is used since they overlap? What VE is used above 4000 rpm and how is it changed? Is the VE adder used somehow here? When PE mode is entered, what defines the VE or is the AFR determined by the "PE Mode AFR vrs RPM" chart?

I helped Ryan get the setup running. It's based on the $A1 code from the DIS V6, so help from people running $8D (TGO), $58, $59, etc. will be limited. You're better off signing up for the GMECM list at http://www.diy-efi.org/

I believe throttle position determines whether idle or main VE tables are used.
The VE adder table is used above 4000 RPM.
In PE, the main VE table is used, but the pulse width is calculated using the PE AFR value instead of feedback from the O2 sensor. Since $A1 only has one BLM cell for the main VE table, BLM corrections to VE are NOT applied in PE.
I think.
This advice may be worth exactly what you paid for it.

quote Originally posted by Will: I helped Ryan get the setup running. It's based on the $A1 code from the DIS V6, so help from people running $8D (TGO), $58, $59, etc. will be limited. You're better off signing up for the GMECM list at http://www.diy-efi.org/ I believe throttle position determines whether idle or main VE tables are used. The VE adder table is used above 4000 RPM. In PE, the main VE table is used, but the pulse width is calculated using the PE AFR value instead of feedback from the O2 sensor. Since $A1 only has one BLM cell for the main VE table, BLM corrections to VE are NOT applied in PE. I think. This advice may be worth exactly what you paid for it.

Thanks for chiming in Will.
Good suggestion about the GMECM site. I have lurked a lot on the ThirdGen site because of the commonality of the 7730 ECM, but their code does seem to have differences that does not apply to the Northstar program

The only thing I can see that might determine when Idle or Main VE tables are used is the constant value: “Max Vehicle Speed for Idle”, currently set at 1.33mph.
So basically at rest the car runs off the idle table, and when moving it runs off the Main table?
The PE enable is definitely determined by TPS and temp – that table is there.
Right about PE – no O2 feedback and the BLM is forced to 128 – so it just runs off the specified AFR in the PE Mode AFR vs RPM table? Why the VE Adder vs RPM table then?


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Daviero - 88 N* GT

[This message has been edited by Daviero (edited 09-04-2010).]

quote Originally posted by Daviero: The only thing I can see that might determine when Idle or Main VE tables are used is the constant value: “Max Vehicle Speed for Idle”, currently set at 1.33mph. So basically at rest the car runs off the idle table, and when moving it runs off the Main table? The PE enable is definitely determined by TPS and temp – that table is there. Right about PE – no O2 feedback and the BLM is forced to 128 – so it just runs off the specified AFR in the PE Mode AFR vs RPM table? Why the VE Adder vs RPM table then?

Throttle position *should* dictate whether the idle or main VE maps are used. Remember that this is reverse engineered (although $A1 is a well documented hack), so something could have been missed. There *should* be a "TPS% for idle" value someplace.
At 1.33 mph it should go from "resting idle" to "rolling idle". This increases the idle speed by a few hundred RPM to provide greater power steering boost and greater stall resistance... e.g. for oozing around a parking lot.

The VE adder vs RPM table is there because the 3.1 V6 for which this code was written makes peak power approximately 4500 RPM. This is the factory code for my Pontiac 6000, which has a WOT upshift at 5200 RPM.

Incorporating significant resolution in the VE tables above 4000 RPM is a waste. When the engine's running above 4000 RPM, the main VE table entry for that MAP at 4000 RPM gets modified by the appropriate entry in the VE adder table. Does the VE adder table contain non-zero entries below 4000 RPM?
Basically, the engineers were betting that the VE table was so smooth above 4000 that the same curve could be applied to all MAP's. They were implicitly betting that no one would spend enough time at anything but WOT above 4000 RPM to notice. They were right.

The $A1 code really is crappy. It's very obviously designed for a non-sporty car to be driven in a non-sporty manner. The unfortunate truth is that it was the closest code to what we needed and the quickest/easiest to get running. Ryan even pirated (I think) the EGR output in the datastream for the RPM/37.5 datapoint that lets the ECM report RPM above 6750 in the datastream.

ftp://ftp.diy-efi.org/pub/gmecm/manuals/1227749/Turbo_P4_Doc.pdf

This is for a turbo, but boost specifics aside, it works exactly the same. The fuel algorithms are outlined in the document.
Basically:

BPW = BPC * MAP * T * A/F * VE * BVC * BLM * DFCO * DE * CLT * TBM

Where

BPW - Base Pulse Width
BPC - Base Pulse Constant
MAP - Manifold Absolute Pressure
T - Temperature
A/F - Air Fuel Ratio
VE - Volumetric Efficiency
BVC - Battery Voltage Correction
BLM - Block Learn
DFCO - Decel Fuel Cutoff
DE - Decel Enleanment
CLT - Closed Loop
TBM - Turbo Boost Multiplier

all of these terms are laid out in the document and calculated according to input from sensors.

The PE mode is entered when some throttle condition is met (I believe) e.g. throttle > 50%, enter PE.
Idle VE is only used when there is no throttle signal present (it's idling)
Main VE is used for everything (see above)
Base pulse constant is used for everything (see above)
Ve adder gets added to the above, I believe.

It's been a while, so forgive me.

Will and Ryan, thanks for you input. In the document you referenced Ryan we see this section:



So the idle VE chart is for throttle closed and up to 1600 rpm and otherwise it is the main VE that is used. No throttle setpoint, just plain closed - this is why there is no constant to be found. This issue seems to be resolved, and will be experimented with in the next tuning session.

The PE chart is definitely enabled at a set rpm, and the BPW seems to be determined by the AFR specified in the PE AFR vs RPM chart.

The VE adder chart has VE adder numbers from 0 to 6400 rpm so this issue is still puzzling.
I'll peruse the document for answers or if you know, please chime in.

The questions seem to be:
When is the VE adder chart used and how?

I think that document will be huge use - I looked all through the GMECM site, but did not see it, or if I did, did not know what it was. Thanks again.

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Daviero - 88 N* GT

quote Originally posted by Daviero: The questions seem to be: When is the VE adder chart used and how?

I'm fairly certain it's used all the time. The reason being is they get more dynamic range to play with... Instead of one cell's setpoint being a single byte (0-255), it's now two bytes. (0-510). Downside is it changes a column, instead of a single cell. I think for the most part you can ignore it. What you want to do is tune roughly with the the BPC, and fine tune with the main VE. After that's good you can go to the PE table. If fuel is close, don't mess with the BPC. It's a coarse adjustment and can really throw things off.

[This message has been edited by ryan.hess (edited 09-07-2010).]

Its been a long while coming, but I have had great success!
A few sessions on the dyno have made a huge difference. A few notes on my experience:
I searched for a tuning shop in the Minneapolis MN and Winnipeg areas (I live in Thunder Bay Ontario) that were experienced with Tunerpro, and/or Northstars but nearly everybody said no and some promised that would give it their best shot bit with no promisses.
I chose to do it locally on a dyno run by 2 guys who have the dyno primarily for tuning his own 9.9 second drag car. They had never seen TunerPro and were more used to the Holley systems, not the GM A1 code that Ryan has used. I avoided travel expense and gained the luxury of time.
I had done plenty of reading and actually showed them the multiple tables and how they interacted. What I did not get myself, we figured out together. They were open that they were learning too, and were interested to do it.
Did it take longer? Yes, but it was worth it.
Did they charge me for every hour the car was on the dyno? No, they were very reasonable. We actually tied the car down Sept 1 and spent a few hours that night, and it sat on the dyno untouched until Sept 17 when we got back to it. We finished up on the 18th and I went and got it on the 19th. Pretty relaxed guys.
The results? Great. The car was running real fat rich, as low as 9.0 AFR when accelerating. No wonder I had a black cloud behind me! We are now down to high 13's and 14 AFR for cruise, and low 12's for acceleration. Power and torque went up considerably.
The numbers? For those who care (I do not) we measured 330 ftlbs wheel torque at about 4600 rpm and 262 RWHp at about the same rpm. I was only looking for improved running, without caring what the numbers were. I have the Deville engine (Vin Y I think?)
Drivability? Considerably improved. Nice smooth power and acceleration.
My recommendations? Faced with this task educate yourself, play with TunerPro to get famiiar with it, get a chip emulator for fast on the run changes and find a dyno shop that allows you to do the tuning with them. You will both learn and you'll enjoy it. No having the car disappear behind a glass wall.
Thanks to all those who have answered my many posts relating to getting this task done. I will summarize what we changed and why for the benefit of those who also need to do this and could use the boost that I got.

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Daviero - 88 N* GT

Sorry I can't contribute to solving your problems, but I just wanted to say that it's great to see that you've been working out the bugs for the VIN Y engine. I'm still sitting on the fence on which management system I'll use (I still have time on my side). Even though I'm leaning towards OBD2 for now, it sure is nice to know that there's a Plan B out there if it doesn't pan out. Just remember that if you get discouraged you've got at least one fan cheering you on over here in the Maritimes! Go Daviero go!

I run $8F on the 7730 so I cannot speak to your specific program. I can say that when in DFCO my a/f ratio pegs full lean as all fuel is cut-off. I can disable DFCO by setting the activation coolant temp to 151*C. Otherwise the stock settings are used. Maybe try to get a copy of another version of A1 to see what they have done? Use the difference checker to look at all the changes.

Had a good drive on a very curvy and hilly road yesterday on northern Minnesota (drove to Ely MN) and what a blast! Even though my driving was spirited with absolutely no attempt at economy but rather for fun and excitement, my mileage was 31.7 mpg (imperial gallons) or 26.3 mpg using US gallons.
I'll work on the IAC and the DEFCO issues which are really non issues in the grand scheme of things.

quote Originally posted by Bloozberry: Sorry I can't contribute to solving your problems, but I just wanted to say that it's great to see that you've been working out the bugs for the VIN Y engine. I'm still sitting on the fence on which management system I'll use (I still have time on my side). Even though I'm leaning towards OBD2 for now, it sure is nice to know that there's a Plan B out there if it doesn't pan out. Just remember that if you get discouraged you've got at least one fan cheering you on over here in the Maritimes! Go Daviero go!

Dave: I have a second 7730 ECM with a harness if you are interested in using one. PM me if you like.

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Daviero - 88 N* GT

quote Originally posted by Daviero: A few issues remaining worth noting: 1) There seems to be DEFCO (deceleration fuel cut-off) in A1 program Ryan used. On deceleration, the AFR actually drops to high 11's and low 12's instead of going to high 14's or low 15's. Changing the fuel VE tables would change the AFR for acceleration and cruise too, so that is not an option. A “negative” ASYNC AE vrs TPS or Delta TPS table would work too, but nothing found. 2) There is a puzzling IAC Motor control issue. With 0% TPS, the IDLE VE table is used, and the IAC is at about 20 steps (more if fan or AC are demanded). No issues here. With throttle applied (TPS>0%) the VE table used is the MAIN VE table is used and the IAC should not try to control engine speed. All is fine if TPS> 2 or 3% and the IAC does fine. BUT: If you open the throttle just a wee bit, (like you would in anticipation of the stop light going green, before clutch engagement) say 1.5%, and you hold it there, the IAC tries to contol the idle and slowly closes, counting down to 0 steps. If you then release the throttle, (like you would if the stop light is longer than expected) the engine stumbles since it has no air! The IAC is closed! The IAC opens rapidly and the engine stumbles back to life with a few oscillations about the target idle speed. There has to be a value to set the maximum TPS for idle, or some other value to de-sensitize the IAC? Any ideas or experience on these two items? They are not huge issues, but it seems odd not being able to address them.

2)
Hex addresses for "is idle fuel" check:

06CE 2E 46 KIDFRPML 1150 RPM ENG SPEED BELOW WHICH CAN BECOME IDLE FUEL FORMS HYSTERISIS PAIR WITH KIDFRPMH
06CF 04 4 KIDFTPSL 1.6 % TPS THROT POS BELOW WHICH CAN BECOME IDLE FUEL FORMS HYSTERISIS PAIR WITH KIDFTPSH

1)
Some DFCO checks:
Address / HEX value / DEC value / variable used
0BA8 24 36 KDFCOMLL 23.6 KPA ENABLE DFCO IF MAP<THIS (LONG TIMER, LOWER HYST)
0BA9 24 36 KDFCOMLS 23.6 KPA ENABLE DFCO IF MAP<THIS (SHORT TIMER, LOWER HYST)
0BAA 60 96 KDFCOMHL 45.8 KPA STAY IN DFCO IF MAP<THIS (LONG TIMER, UPPER HYST)
0BAB 60 96 KDFCOMHS 45.8 KPA STAY IN DFCO IF MAP<THIS (SHORT TIMER, UPPER HYST) RPM * 25 (1600/25=64d $40) 1300 rpm=52=$34
0BAC 40 64 KDFCOSHL 1600 RPM ENABLE DFCO IF RPM>THIS (LONG TIMER, UPPER HYST)
0BAD 40 64 KDFCOSHS 1600 RPM ENABLE DFCO IF RPM>THIS (SHORT TIMER, UPPER HYST)
0BAE 2C 44 KDFCOSLL 1100 RPM STAY IN DFCO IF RPM>THIS (LONG TIMER, LOWER HYST)
0BAF 2C 44 KDFCOSLS 1100 RPM STAY IN DFCO IF RPM>THIS (SHORT TIMER, LOWER HYST)
0BB0 03 3 KDFCODRM 38 RPM MAX RPM DECREASE IN 12.5 MSEC ALLOWED TO REMAIN IN DFCO
0BB1 60 96 KDFCOTO1 19.2 SEC ENABLE DFCO IF CONDITIONS MET FOR TIME >= THIS
0BB2 80 128 KDFCOTM1 25.6 SEC ENABLE DFCO IF CONDITIONS MET FOR TIME >= THIS (IF CONVERTER O.T. PRESENT)
0BB3 1E 30 KDFCOTM2 6 SEC ENABLE DFCO IF CONDITIONS MET FOR TIME >= THIS (IF MAP LOW AND RPM HIGH)
0BB4 01 1 KDFCOINC 1 COUNTS NUMBER OF COUNTS DFCO WAIT TIMER IS INCREMENTED BY IF CONDITIONS ARE MET
0BB5 02 2 KDFCODEC 2 COUNTS NUMBER OF COUNTS DFCO WAIT TIMER IS DECREMENTED BY IF CONDITIONS ARE MET
0BB6 84 132 KDFCORPM 3300 RPM IF RPM > THIS AND MAP < KDFCOMAP, THEN ENABLE THE SHORT DFCO TIMER
0BB7 24 36 KDFCOMAP 23.6 KPA IF MAP < THIS AND RPM > KDFCORPM, THEN ENABLE THE SHORT DFCO TIMER
0BB8 08 8 KDFCOTPL 3 % IF DFCO ALREADY ENABLED AND TPS BECOMES >= THIS DISABLE DFCO
0BB9 05 5 KDFCOTPH 2 % IF DFCO NOT ENABLED AND TPS >= THIS DON'T ALLOW DFCO TO BE ENABLED
0BBA 8C 140 KDFCOOL 65 DEG C IF COOLANT < THIS DISABLE DFCO
0BBB 14 20 KDFCOVL 20 MPH IF MPH <= THIS, INHIBIT DFCO (SHORT, DFCO ON)
0BBC 19 25 KDFCOVH 25 MPH IF MPH <= THIS, INHIBIT DFCO (SHORT, DFCO OFF)
0BBD 22 34 KDFCOVSL 34 MPH IF MPH <= THIS, INHIBIT DFCO (LONG, DFCO ON)
0BBE 26 38 KDFCOVSH 38 MPH IF MPH <= THIS, INHIBIT DFCO (LONG, DFCO OFF)

[This message has been edited by ryan.hess (edited 09-27-2010).]

Thanks for the guidance Ryan, I was hoping you'd post.
I say guidance for now, as it hardly seems like an answer YET - it will take me a while to sort it out, to make it an answer.
But you must have expected some questions:
I think what you are saying is to see if these lines of code are in the BIN?
I have to edit the BIN to add these lines of code?
Is the Hex editor in TunerPro the best editor to use?

Dave.

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Daviero - 88 N* GT

The 3.4L OHV engine out of a '95 Camaro. The 7730 is a natural fit because it runs turbo code, DIS, and uses a knock sensor. I bought an Ostrich, registered TunerPro RT and have been hacking away ever since. I'm such a noob tho.

For instance: Does the main timing table go above 4800 rpm in $A1? In $8F it ends at 4800 rpm and I don't know where it goes above that. My redline is 6350 rpm and I need to know how to adjust timing up that high. The power drops off above 5k even at 10psi so it's either timing or air flow.

quote Originally posted by Daviero: Thanks for the guidance Ryan, I was hoping you'd post. I say guidance for now, as it hardly seems like an answer YET - it will take me a while to sort it out, to make it an answer. But you must have expected some questions: I think what you are saying is to see if these lines of code are in the BIN? I have to edit the BIN to add these lines of code? Is the Hex editor in TunerPro the best editor to use? Dave.

Basically, this is a disassembled binary, and it shows you different variables you can change if you want to. In Tunerpro, you can add them to the definition file to make them easily changed like the VE tables, RSS constant, etc etc.

So, if you want to change any of these variables, and they're not in Tunerpro yet, you'll have to add them.

Say you want to add the "% throttle position below which it can become idle fuel"...

Right click in the constants box.
Insert new XDF item -> constant.
You can enter a title/description, etc.
In address, enter 06CF.
Now, click on 'conversion'
If you want this to display in percent, you'll need to convert it from the raw 8 bit format to a percentage. Well, in 8 bits, you can count up to 255. So to convert that to percent, you take the raw number X and divide by 255. Multiply by 100 to convert to percentage. So your whole equation format should be X/255*100
Save and all that.
Open your bin, and click on the "% throttle position" you just made
It should say 1.57% if you are running the stock BIN. (From above - 06CF - raw value =04 hex = 1.6%) If it shows that, everything is good!

Hope that helps,

edit: you can get the BFUZ disassembly from here for more things to change (I just posted what you asked for, there are thousands and thousands of constants you can play with):
http://www.v6z24.com/jbodyf...wnload,id,32691.html

http://www.v6z24.com/jbodyf...topic,p,1154319.html

[This message has been edited by ryan.hess (edited 09-30-2010).]

quote Originally posted by ryan.hess: Basically, this is a disassembled binary, and it shows you different variables you can change if you want to. In Tunerpro, you can add them to the definition file to make them easily changed like the VE tables, RSS constant, etc etc. So, if you want to change any of these variables, and they're not in Tunerpro yet, you'll have to add them.

Hey thanks Ryan, that makes sense on the first read through. I will try this for sure, and figure out the details as I go. As usual, I'll try to keep questions to a minimum, but also as usual there are likely to be some.....


Any success I have in adding items to the definition file are up for sharing with those who are interested. It just might take me a while.

Dave.

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Daviero - 88 N* GT

[This message has been edited by Daviero (edited 10-06-2010).]

quote Originally posted by Daviero: Dave: I have a second 7730 ECM with a harness if you are interested in using one. PM me if you like.

Dave, check your inbox, I sent you a PM a week ago.

Ok, that explains the VE tables, but where does the EST (main spark) table go when above 4K in the $A1 code?

Sometimes I make it more difficult than it needs to be because I don't understand how things work. It may be that once the main spark table hits 4800 rpm that there is no need for more or less spark advance. Whatever advance has been added is where it stays until the rev limiter kicks in. Points distributors did it this way, yes? All advance was in by about 3000 rpm and that is where it stayed.

quote Originally posted by Hudini: Ok, that explains the VE tables, but where does the EST (main spark) table go when above 4K in the $A1 code?

I actually did not play with spark in my tuning. Knowing there was more power to be had by adding timing, I left it alone for reliability and dependability. In $A1 the spark table also ends early at 4800rpm but the quadrant 2800 to 4800 and 20 to 30 kPA MAP are all the same value anyway, so you are likely right about the last value carrying on. I spoke with the dyno guys about spark and they said for their race car they add timing up to a point and actually start to take it away at higher rpm. Their advice was to leave it as is and go for reliability, and I took the advice. I have read several places that each time you change anything, go back and retune the fuel tables, and this includes timing.
Dave

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Daviero - 88 N* GT

Dave, Sent you a PM about the .bin file, does anyone else have a copy of this bin?

quote Originally posted by Hudini: Ok, that explains the VE tables, but where does the EST (main spark) table go when above 4K in the $A1 code? Sometimes I make it more difficult than it needs to be because I don't understand how things work. It may be that once the main spark table hits 4800 rpm that there is no need for more or less spark advance. Whatever advance has been added is where it stays until the rev limiter kicks in. Points distributors did it this way, yes? All advance was in by about 3000 rpm and that is where it stayed.

quote Originally posted by Daviero: I actually did not play with spark in my tuning. Knowing there was more power to be had by adding timing, I left it alone for reliability and dependability. In $A1 the spark table also ends early at 4800rpm but the quadrant 2800 to 4800 and 20 to 30 kPA MAP are all the same value anyway, so you are likely right about the last value carrying on. I spoke with the dyno guys about spark and they said for their race car they add timing up to a point and actually start to take it away at higher rpm. Their advice was to leave it as is and go for reliability, and I took the advice. I have read several places that each time you change anything, go back and retune the fuel tables, and this includes timing. Dave

Think about the engines that $A1 was originally used on... peak power @ 4500ish with auto trans shift point in the 5200-5500 range. IE, peak power was within the bounds of the table and the engine didn't spin too far off the end. There isn't much timing change required beyond peak power, generally, so it was ok for the application.

There is a link on this page and some good info on $a1 also
http://www.robertisaar.co.c...les-Information.html

[QUOTE]Originally posted by jdv:

There is a link on this page and some good info on $a1 also
http://www.robertisaar.co.c...les-Information.html[/QUOTE

Is the Vin Y .bin on this site? I tried the A1.adx file, but when I convert it to a .bin to burn it to a chip, it says it is too large.
Only other northstar thing I saw was a link to Ryan's page with the Vin 9 code that I am using now...