Finally got my PDA and PocketLogger software up and running. Did a series of data logging to see how SAFC corrections effect timing. Results are interesting since it is believed that taking fuel away with an SAFC will indirectly advance timing. To what extent it effects timing is not really known though.


Results I got are good and bad. From my logs, timing doesn't seem to be effected too much at all from -% SAFC corrections. And the small difference in timing there was indicates that -% SAFC corrections may actually reduce timing advance, which goes against conventional wisdom.

The good being that I have not been adding in timing on a turbo car that is already runnnig stock timing. That has always been a concern of mine

The Bad being that I was thinking about setting up my fuel system so that I would be adding fuel via the SAFC and could actually pull some timing that way. Although I did not try the reverse, I would assume the results would be similar

Raw Data

No SAFC corrections

Time,RPM,Timing
00:02.53,3063.0,25.0
00:02.90,3138.0,25.0
00:03.26,3225.0,23.0
00:03.63,3325.0,21.0
00:03.98,3400.0,20.0
00:04.34,3513.0,16.0
00:04.69,3575.0,14.0
00:05.07,3713.0,13.0
00:05.42,3838.0,14.0
00:05.79,3938.0,14.0
00:06.13,4038.0,15.0
00:06.50,4150.0,16.0
00:06.86,4238.0,16.0
00:07.23,4313.0,17.0
00:07.59,4413.0,17.0
00:07.94,4563.0,18.0
00:08.30,4675.0,18.0
00:08.65,4775.0,19.0
00:09.03,4888.0,19.0
00:09.40,5000.0,20.0
00:09.77,5113.0,21.0
00:10.14,5213.0,22.0
00:10.48,5300.0,23.0
00:10.85,5400.0,23.0
00:11.22,5513.0,23.0
00:11.59,5613.0,23.0
00:11.94,5713.0,23.0
00:12.31,5813.0,23.0
00:12.67,5888.0,24.0
00:13.03,5988.0,24.0
00:13.39,6088.0,24.0
00:13.76,6188.0,24.0
00:14.11,6200.0,24.0



SAFC corrections 7%-13%

Time,RPM,Timing
00:03.26,3025.0,28.0
00:03.63,3125.0,27.0
00:03.99,3213.0,23.0
00:04.36,3300.0,24.0
00:04.72,3400.0,21.0
00:05.07,3500.0,19.0
00:05.44,3613.0,15.0
00:05.80,3725.0,12.0
00:06.15,3838.0,12.0
00:06.53,3950.0,12.0
00:06.90,4075.0,13.0
00:07.25,4188.0,14.0
00:07.61,4300.0,14.0
00:07.97,4425.0,15.0
00:08.34,4525.0,15.0
00:08.69,4650.0,16.0
00:09.06,4750.0,17.0
00:09.40,4888.0,17.0
00:09.77,4963.0,18.0
00:10.14,5063.0,19.0
00:10.52,5213.0,20.0
00:10.88,5300.0,21.0
00:11.23,5425.0,21.0
00:11.59,5513.0,21.0
00:11.94,5613.0,21.0
00:12.31,5713.0,21.0
00:12.68,5813.0,21.0
00:13.05,5913.0,22.0
00:13.40,6000.0,22.0
00:13.76,6100.0,22.0
00:14.11,6150.0,22.0



SAFC Corrections 12%-17%

Time,RPM,Timing
00:03.61,3038.0,28.0
00:03.97,3113.0,27.0
00:04.34,3188.0,25.0
00:04.71,3275.0,24.0
00:05.07,3350.0,21.0
00:05.42,3463.0,19.0
00:05.79,3563.0,17.0
00:06.15,3675.0,15.0
00:06.52,3775.0,13.0
00:06.88,3888.0,14.0
00:07.23,4000.0,14.0
00:07.59,4100.0,14.0
00:07.94,4213.0,15.0
00:08.31,4325.0,15.0
00:08.68,4463.0,16.0
00:09.03,4563.0,17.0
00:09.39,4675.0,17.0
00:09.76,4775.0,18.0
00:10.14,4863.0,18.0
00:10.51,4975.0,20.0
00:10.86,5100.0,22.0
00:11.22,5188.0,23.0
00:11.59,5300.0,24.0
00:11.93,5400.0,23.0
00:12.31,5500.0,23.0
00:12.67,5600.0,22.0
00:13.02,5675.0,22.0
00:13.39,5775.0,22.0
00:13.75,5863.0,23.0
00:14.10,5963.0,23.0
00:14.47,6038.0,23.0
00:14.84,6088.0,23.0



The graph was done with taking a 3 run average of each.

 

Interesting stuff. I wonder if it would still hold true for larger correction factors like 30-40 percent.

 

Mike, I'm very interested to know how it will affect timing when you actually add fuel back in. Like your setup I'm at around -8% correction in mid range and -2% above 5800 rpm to get a 11.0ish A/F. It would be nice to find out which way would be a better route to go for us who are using stock ecu still. I have to install my J&S to pull some timing above 10psi but i have yet to venture into that much boost. keep us updated!

 

I didn't do any +% corrections because with no corrections I am at a very low 10:1 ARF and inorder to do a valid test I would need at least a +10% correction and that is putting me really, really rich....don't think it matter too much though. The main reason I didn't do + corrections today was that the 12 4th gear back to back pulls at 120+ mph was pushing my luck with my tranny and the cops. (all pulls done on a 4 lane divided highway in the middle of nowhere)

 

Understandable on those runs better not press your luck.
Do you have a AFPR? I was thinking of maybe lowing my base fuel pressure just enough to get around 11.7 to 12.0, add +% via SAFC and see how that turns out. I don't if that is the safest route since I dunno how reliable SAFC in cosistency plus inorder to get +10% correction, the base A/F must be pretty high like 12.5ish.
If using +% can indeed retard/pull timing, it would be better as long as boost spike is kept to a minimum to avoid suddenly going lean.

*edit* are you running low 10:1 AFR due to you running 550cc? I ran 500cc because of your brother's recomendation and I saw 10:1 on a around stock FP. I lowered it a little more to get close to the 11:1 mark and fine tuned it with the SAFC.

 

Actually with no SAFC corrections I am below 10:1 in some places but since I can't get a reading below that I am not exactly sure how rich it really is. I run 550's on 50psi of base fuel pressure. No AFPR for me.

I was thinking of trying to lean it out to 12.5 or so then add fuel in, thinking I could pull some timing and maybe run a bit more boost. But in all honesty I dont need/want more power than I am making now and I am really pushing the limits of this tranny.

 

hey mike good info my stocker seems to be running fine and car seems to be moving a lot faster, ima get it dynotuned this week and in the 5th ima gonna be in the dyno. I need to get a datalogger.

 

Thats some excellent information right there. Anybody care to do this to a NA car? That would be awesome.

allen

 

Very intersting results.

I have a SAFCI tuned to around 13.3:1 AFR from a high 10:1 to 11:1 AFR. I have a Consult scanner that I still have to hook up to my Carpc so I can log but I did test it out a while ago

Not that many points but its basically the same timing Mike is at.

No correction
RPM Timing
4050 15
4513 18
5000 21
5550 23
6000 24

As soon as I get a chance, ill log with -% correction (23% around 4000 RPMS) and see if I get the same results as Mike.

 

Stock ignition MAP and A/F for engines series VQ (from ROMs ECU):
if DATA>128, Ign.=(DATA-128)
Blue - close loop,
Red - open loop

VQ30DE




VQ25DE




VQ20DE

 

Hello their!!!

 

Ummm...is that a ROM editor program for a VQ30DE???

 

Where did you get those?

 

I have had this program for a while now and have dumped my ROM but don't have the adr file for the VQ30.

Maybe Alex-Angarsk will give it to us.

 

What is the ADR file? I take it you cannot save to our ECU's. I have read you can save the edited roms to OBD-I ECU's.

 

I believe the ADR file tells the program where to look in the ROM dump for the timing, a/f etc. Without thats its all gibberish.

No you can't save it but it may be possible to replace the ROM with a R/W one that we can then program or have a daughterboard which allows you to switch between stock ROM and a modified one.

 

It will be too much work to repace the ROM with and EEPROM IMO. Lots of precision soldering. I would not know how to make the daughterboard work. Maybe I need to learn more about electronics.

 

Some guys just pay an electronic shop $30-40 to remove the ROM and put in a socket (if you don't feel comfortable around a solder sucker or braid) and then you can change it easily. This of course all depends on if its possible to get it to work, don't think that has been proven.

 

If we can find out what chip stores this information in the ECU, we can crossreference some numbers and find an EEPROM to work with our ECU. And we can find the DIP socket that fits it.

 

This is what I was referring to on eng92's thread about needing to be able to look up the correct addresses and scaling factors to be able to make sense of any ROM dump. The electronics isn't the limiting factor here so much as this stuff I think. Replacing chips/adding romulators is doable for any knowledgeable electronics technician. The key is being able to read and write the hex information correctly.

Did not know there might be an ADR file already available though!!! I'd definitely like to have that file if Alex-Angarsk is willing to share.

I wonder if there is any differences between North American market and overseas ECU's. Ie- if they share the same type and number of tables, address locations etc. Given the emissions equipment and other differences (MEVI etc) things could be slightly different. Maybe not; it would be interesting to see.

 

They do not have as many O2 sensors. The only have one IIRC.

 

We've gotten a pretty good price for a datalogger as long as we get 10 people over in the 5th gen section.
Autoenginuity for $180 shipped.
I was unaware they had a scantool with output capabilities for Nissans avail. (except obviously the Consult II.)
I do a little datalogging, am N/A. I use the info Primarily for diagnositcs purposes...
This program highly interests me..
This program changes the Rom while the datalogger is hooked up, but does not save?? Is that what I'm seeing?....If that's right then I know a few DSM guys who are big into tuning and may be able to help create an updated E-ROM or E-PROM if demand was big enough.
I haven't been inside our ECU, but am guessing the ROM's are soldered in as stated above, not just chips that come in/out like some vehicles?
Also what datalogger are you using this editor with?

 

I don't know if its possible for any OBDII reader on a 4th Gen to dump the ROM. I have 3 programs that work with my OBDII adapter and none of them will.

Its my Consult I adapter that does that and I use either Calumsult or DataScan to dump the ROM.

 

A word of caution: I have tried to use the AutoEnginuity on a 2000 Max and it wouldn't work. You may want to verify first if it does...

As Jime said, the interfaces we're talking about are via the Consult I protocol, not OBDII. Consult I is only applicable pre-2000, therefore only 4th gens and earlier can use these programms (I have OBDScantech, DataScan, and CalumSult). They are essentially better dataloggers than the standard OBDII fare but they can also temporarily adjust certain parameters, perform active tests such as power balance tests, and can dump the ECU ROM to a .bin file, but cannot write back to the ECU. To do that you need to make hardware modifications.

-----------------------------------------------------------------------------------


Jim, to add to my last post above, I can forsee complications with this due to OBDI/OBDII. These Consult I scanners and rom editors etc were all developed on Nissan cars using OBDI ECU's. From what I understand this also includes the Maximas/Cefiros/Glorias (with either VQ30DE or VQ30DET) if we're talking about non-US/Canadian markets such as Europe, Asia, Australia etc.

If all these ECU's are OBDI based, they are likely set up very similarly in structure. That is, the number and type of maps (2 fuel, 2 timing for hi/low oct and normal/knock etc), the VQ curve (which is really the VE curve), K scalar value etc, all seem to be fairly commonly used across any Nissan OBDI ECU. SO all of these programs like ROM Editor, Live Edit etc are programmed with this in mind. The OBDII ECU's may have a different kind of structure. The map types may be different, there may be additional modifying maps and/or individual parameters etc. If so, getting a program like ROM Editor to display all this correctly would require some custom set up via editing of the ADR file, and it is dependant on how much the program will let you add even. I don't know. Plus there's still the headache of trying to develop an ADR file for the OBDII case - I would be really surprised if the addresses given in the OBDI ADR file are the same on ours.

That's not to say that what Alex posted above isn't useful. I'm assuming that ADR file is off an OBDI Maxima (if it's in Russia), but even so it could be a good indication of what the stock fuel and timing curves are likely to be on an OBDII Maxima. And also this information is a good indication that converting back to OBDI by using a foreign ECU such as the Gloria's may open up a new tuning option (providing emissions regulations where you live allow it). The second part of the equation would be developing the hardware solution to go with the software.

BTW, do you have the latest ROM Editor version (48E)? I only have 41E and can't get the new one as the website is down for who knows how long... Live Edit is a nicer program in some respects.

 

Dan I wonder how hard it would be to get an OBDI ECU? Not too worried about emissions I just had mine done so have 2 years. I only have 41E as well so I am no help to you.

Going to start looking for an ECU.

 

Can you email me the bin file Jime? kevlo2000 at yahoo com

 

Yeah I know you're not worried about emissions, I was just making a general statement since in most places it is illegal to convert 96 and newer back to OBDI and some places plug into your OBDII port for emissions tests too.

I would PM JClaw about getting an ECU... I believe he knows of someone who just got a Gloria one for $150 CA or so. Where from I don't know.

And if you wouldn't mind, please send me your .bin file also ... dvrditar at hotmail dot com. At some point if I get to it I might compare it with my 96 JWT and stock 98...

 

Intresting, I have gotten feedback from alot of people at my school using this brand and have never heard of any problems.
What OBD II software would you recommend??
I'm almost positive none of them have output command options for Nissan, and this brand is the only one I know that can datalog more than one sensor on the same graph.
Subscribing.

 

Don't get me wrong, the AutoEnginuity has a lot of features and I've used it on other cars (non-Nissan) with success. As far as reasonably priced dataloggers go, IMO the top 2 choices are Auterra and AutoEnginuity.

All I'm saying is for some reason I had problems with the AutoEnginuity specifically on a 2000 Maxima. It would not connect properly. I believe that there was a bit of a crossover point in 2000 where Nissan transitioned to new protocol and IIRC the 2000 Maxima is one of the cars listed by the EPA as not being fully OBDII compliant even though it's supposed to be. In fact I might have seen this info on AutoEnginuity's website even. Did you browse through all their information pages (FAQ's etc)?


EDIT: I can't seem to find it on their website anymore and I also see there's a new version out and one of the release notes is "Fixed Nissan 00 - 01 DTC retrieving issues" so maybe it works fine now? The last version I used was 3.5 and they're up to 4.01 it looks like so I'll have to DL it and try it out on a friend's car.

 

The would be awesome. Could paypal you a few dollars for gas if you wanted..
Yeah proscan, etc are out of the question. It's funny you mention Auterra though, because that was one of the otehr ones I was looking out, unfortunately (IIRC) auterra's program doesn't allow datalogging two sensors on one graph, that's kinda what sold me on autoenquinuity..Not to mention the fact that AutoEnginuity has BT technology.
(EDIT: after looking at auterra's site, I'm noticing that they do have the ability to graph to sensors on one graph simutanuously.I can't remember now why I wanted the autoenquity over the auterra.)

 

Dan does the SpeedTracing program work ok on the AutoEnginuity or does it have problems doing that stuff like the Auterra because of the slow ECU speed?

PS Will email file today.

 

Message from yahoo.com.
Unable to deliver message to the following address(es).

<kevlo2000@hotmail.com>:
65.54.244.40 does not like recipient.
Remote host said: 550 Requested action not taken: mailbox unavailable
Giving up on 65.54.244.40.

 

Got the file, thanks.

Yeah unfortunately on the 4th gen it won't work because the ECU is such a dog. On faster ECU's though it wouldn't be a problem. The scan tool itself even has problems staying connected sometimes (well the older version anyways, haven't tried the new one yet).

 

Looks like some great info guys. I'm just wondering whats with the actual timing #'s. Is 24 degrees normal for 6+K? I need to read through this when I have more time.

 

Hello. I ask to forgive for bad English.
First I have found VQ30.bin in WEB http://alex-angarsk.narod.ru/avto/vq30.a32.bin, and with the help of the program romscan have found Hex the address of storage of the basic maps: VQ, Ignition, and fuel http://alex-angarsk.narod.ru/avto/vq30de.adr.
Approximately since 1994 Nissan uses new architecture ECU for V-6 (engine KA24DE as). The new formula (is not present in ROM Editor) is A/F=14.7 (DATA/128), the formula of ignition has not changed. At research with use Consult - PC the interfacethe ECU Appeared what to read DUMP on OBD-I and OBD-II it is possible only the program http://homes.jcu.edu.au/~jc118216/tecu/tecu.zip.
Now I have copy ECU VQ25 NISSAN-CEFIRO1997 for experiments. Main Hitachi H8/536, processor is a 80-Pin QFP package

MAPs are On-Chip ROM H8/536, I plan to add and use external memory. It seems difficult only in the beginning. (For example http://www.sxlist.com/techref/hitachi/h3320.pdf). I hope, that MAXIMA 4 gen. (and 5) has same architecture ECU.

 

Suppose to be at yahoo dot com

 

romeditor19848e http://www.nissan200sx.ru/download/romedit.zip

 

Alex-Angarsk: Thank you very much for the information. I will check into it further.

5thgenmaxima: Had a chance to try the new Auto Enginuity version (4.0.1) out today at lunch and it seems to work fine now on a 2000 which is good news!

Broaner: I'd say 24 deg at 6000+ rpm is normal for the stock ECU. JWT only advances to about 30 or 31 (+6) so it sounds reasonable to me. Check out eng92's work; his logs support this... http://forums.maxima.org/showthread.php?t=457652

 

Just look at the logs at the top of the thread. 24 degrees of advance at 6K rpms

 

ThankYou dandyMax. I really appreciate it.