User1

Yep, thanks for the info!

Not sure how I missed these last few posts. Slamrod got ahold of me about the MAF I recommended. Some of you know I have been dealing with millisecond-long duration, high RPM knock between WOT upshifts since the swap. I did everything from new knock sensor, Walbro fuel pump, another ECU I bought off Krismax, played with timing in NDSII, checked for loose everything, even took a Nissan mechanic for a ride and reproduced the issue, all to no avail. Car ran perfectly fine otherwise. I've just been going easy on the car as my gut feeling has always been knock and didn't want to damage anything.

Today I pulled the Hitachi MAF0095 out and threw in the old MAF that came with the old motor, did a few pulls, knock is gone and I have also noticed a slight overall gain across the board. I have an order in for the Hitachi MAF0099. I don't even remember why I put a new MAF in the motor during my swap. I didn't know anything about the history of the old motor I think and just wanted new sensors for the swap motor.

That said, how much knock can these motors handle before they suffer damage? Not saying I floored it often, but I have done so to test once in a while and especially after each time I did something I thought might remedy the situation. I'm sure it's fine, I just hate that I ever heard it at all!

timbarry

Same reason as I did when I did my swap. It looks identical to the others which then makes it look like the best priced genuine Hitachi MAF for our car. Looks like Rockauto has it right. Lucky I had my AF meter hooked up to even notice this. Then I could really see it in NDS2 data logs. Experience is the best teacher after all. Glad we could all come together on this.

User1

Me too! Thank you so much! But where the hell where you a year ago!!!!

timbarry

Lol I just went through all this late last year. Same with my Rom Raider adventure. Only noticed to say anything reading this thread. It was fate I guess.

User1

How long did you knock your engine? I would estimate I've got about 5 seconds total with knock under load. Think I hurt anything? Old engines (grampa's 350, etc.) can knock for years and oh well, nothing you could do about it anyway, but these late model, tight-tolerance, high tech motors, not sure how they respond to that kind of abuse!

timbarry

It wasn't that long maybe a few days to a week. I mean I could feel it at first then saw it on the AF meter. Once I saw it go lean I stop WOTs like that. I think you are ok.

User1

Agreed.

User1

So I've put about 45 miles on the car driving back and forth to work last night. I gotta say, it's like driving a different car. This old MAF makes me feel like I've been driving a sick car for the last year. The car now feels like it's getting the fuel it needs. It's more responsive, has more torque, and powers through redline shifts with no knock or tapering off at high RPM. The difference is notable.

I apologize for suggesting the wrong MAF, but a great lesson was learned here, and I truly appreciate the work you have done, Slamrod! And thanks to the knowledgeable folks that have participated in this thread to get him/us to this point. This is really important and I hope anyone who has issues or needs MAF info finds this thread as it's the only one with this critical info.

Slamrod

iTrader: (11)

So, its been a while since I had anything to update. Lots of good news!

Unstable MAF voltage? GONE.
Idle and stalling issues? GONE.
Twitchy AFRs? GONE.
Stuttering, hesitation, and overall roughness? GONE GONE GONE.

All of my issues were from using the wrong MAF sensor. As it turned out, the "original" sensor I had AKA the one on the car since I bought it, was also the wrong sensor. I cant even imagine how frustrated I would be trying to figure out what the problem was, had timbarry not stepped in and pointed out the issue. Anyways - I ended up grabbing a 3.5 inch intake from Nisformance, along with a slot style MAF sensor. Car runs beautifully now! I managed to get a very basic tune that allows full function of the car with no issues or anything to worry about. To be 100% honest, right now Im kinda feeling lazy so Im not going to get into detail on the numbers and everything, but Ill add a post later with what I did and how I got there - I keep a journal with info about every single tune file I make written in it, that way when its not fresh in my memory down the road, I have every little detail accounted for in my notes.

One issue I am noticing however - my mTP100 seems to be off. I scaled it for the new injectors (from 19.97ms >>> 10.03ms, using 560cc/290cc) but it seems that I am accessing 100% load way too easily. Just at idle its at 25% load according to NDS2, and I am able to make it hit 100 load when I am cruising just by going down on the throttle a little, perhaps not even 1/4 of total pedal travel. This is suggesting to me that I simply need to tweak my mTP100 a little by making it slightly longer, maybe by 1ms? That part is pretty straight forward - my question is how do I know when my load scaling is good, since scaling based on injectors seems to have given me an IPW that is a little too narrow? What targets should I be looking to hit (ie; ~16 load at idle, 100 load at WOT, etc etc). Just looking for a somewhat "scientific" method for determining this rather than just experimenting blindly.

I cant even express how happy I am that Im finally over this hump though! This stupid MAF issue had been holding me back and making progress impossible all along. Now that Im actually working with a fully functioning car, this tuning stuff actually seems WAY easier than it appeared when I first began this journey. So basically, so far at least, SUPER steep learning curve, but once you climb it, its flat as kansas! Up next - going to continue tweaking the K value, although it seems very close to where it should be already. After that, Ill likely be fine tuning further by using the Fuel Correction table to make adjustments in specific areas, as needed. I have some more plans in the works too, that will let me to make the most of this tune - more on that when the materials needed to make it happen arrive in the mail. Until my next update!

Child_uv_KoRn

iTrader: (7)

So is my G35. I still don't think it matters on manual at all, b/c the ECU cares about RPM, MAF V and TPS. And you'll definitely hit high load if pushing the throttle in high gear/low rpm. So, sounds like it's working to me. Do a 2rd gear pull from low rpm, drive normally and check it.
I just checked my logs. It's a bug at idle. It's not 25% at all. Normal driving is from about 11-30% load.
I hit 100% load at 3.1V pedal pos (WOT is ~4.3). It was ahead of TPS.

The hard part is manually calculating maf table....just did that last night lol. That's what matters for AFR accuracy.

User1

I'm sorry!!!!! Bye!

Child_uv_KoRn

iTrader: (7)

Leave me in your will.

freezer

Remember, the load you're logging has nothing to do with mTP100, the Load Base Fuel Schedule map determines the load you're logging. If you change the entire LBFS map the same percentage as mTP100, you should be in business.

Whatcha working on?

freezer

I don't understand why people do this with the MAF table. I've never touched the MAF table other than when I swapped the sensor type. There's a nice 16x16 fuel comp table that is made for fine tuning. Don't have to worry about creating a wonky MAF table.

Child_uv_KoRn

iTrader: (7)

It's not wonky, it's nearly 100% accurate. Fuel compensation only works so well given the resolution and varies some in different conditions. Fine tuning means 1-2%. How far are you "fine tuning" in a 4" housing (and across how many load cells)?

This g35 is S/C and maxed the maf at 5600 rpm. I made a voltage divider and dropped it 20% (overkill lol), so rescaling is 100% required. Without rescaling, AFRs were all over needing up to 25% correction and started causing driveability problems just from warmer air.
Now? Most of it is dead on and I did a few 1-2% adjustments to maf table. Fuel comp is 100 across the board out of boost (in boost is different b/c still returnless).

Remember, maf table is nowhere close to linear. That's why so many problems can be generated from altering maf V.
If your particular setup doesn't have any swinging AFRs, then, sure, it's fine. Otherwise, scale the goddamn maf.

Slamrod

iTrader: (11)

The reason im concerned - doesnt the ECU use load to determine where on the Fuel Correction table it needs to access? All my corrections are set to 100 (aka no adjustments) so right now it has no effect regardless, but I would like load to be figured out before proceeding.

What do you mean by manually calculating the MAF table? How does one do that? I understand the ‘why’ but I cant find any information on what that process involves, al the info Im finding mostly pertains to scaling for diameter changes. Could you tell me a little bit about it, and how one can determine whether or not they need to do it/when do they know its right?


I scaled the LBFS the same as I did for mTP100, so that factor is accurate in terms of reporting calculated load. It just seems that im hitting 100 load too easily.

As far as what I am working on... got this little guy in the mail today.


Im sure theres better models, but for $12 shipped, why not just stick with tried and true? As of now, im just going to monitor through headphones. At some point, I would like to investigate making use of the extra knock sensor on the HR swap motor by wiring it up in such a way that the signal can be captured and analyzed with audio software on my laptop, that way I have a visual aid to supplement what I am hearing. Still have a bit further to go before I start toying with timing though lol.

​​​​​​​

Child_uv_KoRn

iTrader: (7)

He says no http://www.christurnbull.com/project...v-tuning-350z/ Auto uses to adjust shift pressure.

Idk the differences between round and slot maf (not much but some, saw some stuff on romraider forum). That in itself probably needs slightly scaled and then for housing.

How does the table show in romraider? It's easy on uprev now, b/c it's shown as percentages.

freezer

You're not differentiating between the load Slamrod's measuring determined by load base fuel schedule, and the cylinder filling efficiency determined by mTP100. The two are very closely related and that's why it is important to scale both equally. The ECU uses the cylinder filling efficiency for many important maps, including timing, fuel target, and cam timing.

The LBFS table is scaled a bit higher for a 7th gen Maxima than the 5.5 gen. So you might hit 100% a bit early, but it won't need drastic changes in addition to what you've already done.

freakyvq

when using only large MAF Housing, you need to touch mTP100 Scalar or BFS Table?

freezer

No. These parameters are related only to the injector size and the effective displacement of the engine.

freakyvq

Thanks a lot! I only tuned MAF Table without increasing K Multiplier, car runs smoothly, is there any chance I lost power because of not touching K Value?

Slamrod

iTrader: (11)

K and MAF scalar are multiplied together as part of the formula that the ECU uses to determine injector pulse width. You can use either that you prefer but to keep it simple it makes more sense to tune MAF changes under MAF scalar, and injector changes under fuel scalar/K-value. In your instance, since you already accounted for the changes using the MAF scalar, you dont need to touch K. Alternatively you could have used K to tune, and not have touched MAF scalar, but it would have produced the same result, since it all gets multiplied together anyways. You dont account for it twice though.

freakyvq

I tuned MAF Table manually and then with tools ( djamps php tool and LogAnalyze ), didn't touched MAF Factor because I was maxing out multiplier ( 190 x 1.53 = 290 ) I cannot input higher then 255 in MAF Factor

Slamrod

iTrader: (11)

You can get around the 255 MAF scalar limit by inversely scaling K, since they get multiplied together to determine fuel delivery. For example, you could multiply your MAF scalar by 0.5, and multiply your K-value by 1.5; this just moves the numbers around the formula without changing the end result. Doing this gives you way more room to work with in the MAF scalar. Really no benefit at all though, other than allowing you to keep MAF changes under the MAF scalar and fuel changes under the Fuel scalar. Its purely for organizational purposes.

Can you educate me a little on how one manually calculates their MAF curve? Totally foreign concept to me but Ive seen it mentioned a few times, definitely something I want to explore.

freakyvq

Well first I multiplied entire MAF Table to 1.53 ( calculated with "Area of circle" method ) , then I dropped that Idea because in some areas it was too rich, then I multiplied it to 1.25 and flashed, afte that car was lean but drivable. did some easy pulls ( closed loop ) and added logs to djamps tool. then logged with uprev cable and corrected with LogAnalyze

P.S

Thanks for clarifying. that means for final fueling doesn't matter what you dial in K or MAF Factor, both affect final fueling the same way ? I mean both increasing IPW?

Slamrod

iTrader: (11)

Both scalars are used in the same exact equation that determines fueling. When you are changing something like MAF diameter, you are changing the numbers that get plugged into that equation. Since both scalars are multiplied together in the equation, it doesnt really matter where you plug the numbers in, as long as they are being plugged in - if that makes sense? Its like saying (10x2)x(5) is the same thing as (10)x(5x2), since both equal 100 no matter how you move the numbers around.

95naSTA

iTrader: (10)

The way I've read and followed for tuning with Uprev on my G is that you want to get in the ball park with the K multiplier first then fine tune with the MAF table. That's only if you messed with the MAF diameter or injector size. If neither changed, you can get where you need to be with the MAF table.

Child_uv_KoRn

iTrader: (7)

You can't multiple the whole table or even part of it. The sensor doesn't output linearly. That's why you can't do a fixed percentage (I was trying to explain that in a previous post). Idk what the equations are to do it without reference V. But if you log with stock intake, then upgraded and compare the two, you can adjust the corresponding cells (starting at idle and working your way up). 5V will be something like 50% on a 4" intake (if i'm not totally retarded). After that I believe you should be able to multiply K (from the initial value when you started with just adjusting for injectors) by double the percentage of V drop from max maf V between intakes. That should get it running enough to adjust to 0 for idle.

freakyvq

nice write up! I only have 3.5” OD maf housing, I decided not to touch anything but maf table, just adjusted some areas to make car drivable and then tuned with utilities. didn’t touched fuel compensation either yet, all set to 100%, I was digging and dunno if I am wrong/right about compensations separated in closed and open loop areas, found map that is for Open Loop Enrichment I guess, can share for you guys to look at it

Slamrod

iTrader: (11)

Is this possible without having data from the stock MAF setup? I dont have a stock MAF sensor, and I am not willing to spend hundreds buying one, so I dont know what my MAF values looked like before I increased the intake diameter. Does this mean I am basically SOL, or am I misunderstanding? I tried using that djamp tool, but nothing happened when I uploaded a log, do you need two for it to compare between?

freakyvq

Maybe you can use Balaguru tools too?? or just this formula

Slamrod

iTrader: (11)

Absolutely fascinating to me how all this math goes into getting the motor to run correctly. Ill have to play around with that at some point later. Another question for you though - I get the impression that in order for this to work, that I would need to go back to stock injectors? It says to not touch the K-value, but with my bigger injectors, that simply isnt possible, since my K-value must be reduced to account for all the extra fuel. Will this still work for me with the bigger injectors? Or does that introduce too many variables?

Child_uv_KoRn

iTrader: (7)

In your case, I would just do it with stock diameter intake as is. The maf outputs are close enough that you can tune it in the maf table later.
That tool is for uprev logs, but I ASSume you should be able to edit the headers, so the tool can read it. https://maxima.org/forums/5th-genera...ml#post9220153
I assume that's what freakyVQ has been doing.

I'll admit, idk **** about the open source stuff. I just learned how to tune with uprev, but a lot of it applies. Unfortunately, it's just not 1:1, b/c of uprev's GUI.

You'll have to interpolate a lot, but it'll be very close. Start at your new idle V and match that to your stock intake and use that maf value.
Again, I'm math tarded, but here's how I interpolated: Let's say your idle is 1.06V. The closest maf table V without going over is 1.04. The increments are in .08V. 1.06-1.04=.02V. 0.02V is 2/8 of the voltage increment. Multiply 1.04V maf value by 25%.
I really hope your voltage isn't erratic, still LOL. Otherwise, I guess you'll have to do some fancy smoothing to get some usable values. Worst case, I guess just just use tenths and interpolate some more. All of it can be tuned out, anyway, plus fuel trims can do the rest. If you get it within 5%, then nbd if you ask me.

I suppose you could do multiple runs and just average/smooth the best you can.

I would love to know a better way. So call me a retard and correct me, plz

I was talking about whatever the calculated load table is...anything else idk and wouldn't touch it. Maf and K is all you should need.

freakyvq

can you post your sample log that you are uploading to djamps tool?

User1

Are you 300/300 yet?

Slamrod

iTrader: (11)

So I've had my hands full with some other stuff lately, plus I was just really happy to have my car driving with no issues for the first time in god knows how long, so I kinda put this thing on the backburner. Today I adjusted my load scaling by adding 10% to my mTP100 (Injector Pulse Width, from 10.03ms to 11.03ms) and Base Fuel Schedule, since it seemed like I was getting to high loads too easily. Wow what a difference! Definitely a lot more torque according to the butt dyno. Almost feels like how it does when you go from having a bad knock sensor to a working one. I think its possible that I am at or very close to the point where fueling is optimal... although how would I know? I am getting a nice, crystal smooth flat AFR when I go into WOT, with AFR sitting around 12.5-12.8 thereabouts. I still have no clue what "optimal" AFR is supposed to be, or how I could find out without having access to a dyno - but since my Fuel Targets are set to 12.54 AFR, everythings working as intended in that area. As for idle, seems good to me? RPM is stable, AFR is stable (Fuel trims are in the 5% range which is perfectly normal I believe).... so... does this mean Im good? Is it really this easy?

This whole MAF scaling thing with the DJAMP tool, how would I know it needs to be done? Everything seems to be working for me, but Im sure I could simply be missing something. I would like things to be optimal, but... I dont see any issues that I would be fixing? What would be the symptoms of MAF table being off? As per Freezer's advice, I simply copied the MAF table from a 350z (or a 6th gen maxima, i dont remember) to generate a MAF curve and then added 15% to the scalar - this seems to work perfectly fine for me. What would I need to look out for to demonstrate my MAF table is or isnt effective?

User1 - Highly doubt I am 300/300 lol. But I think I am just about done tuning fueling, which to me is such a massive milestone. If that is indeed the case, I need to get around to building my knock monitoring device so I can start playing with ignition timing. I dont plan to dyno the car until I feel that I have a very solid tune to work with, so I wont be able to tell what its actually putting down until then. I need to convince my buddies to chip in so we can do a dyno day, that way I wont have to pay for all of it lol.

Slamrod

iTrader: (11)

So this has been on the backburner again for a while. Figured I should probably get my *** in gear and start picking away at it. I definitely need to work on my MAF table - my AFRs have notably changed since the weather has gotten warmer. However I am in a bit of a pickle - the MAF calculators I can find (ie; DJAMP MAF tool, etc) are designed for uprev, not NDS2, which is what I have been logging with. I cannot figure out how to adjust the headers in my NDS2 generated logs so that the MAF calc tool will recognize them. Any suggestions on how to proceed there?

My second issue is that I cannot get the RomRaider logger to work - idk if I had it down and forgot or what, but its not recognizing my openport2.0 cable. Im using windows 10, and its showing under device manager as a "vehicle passthru device" rather than under the COM ports. The logger is giving me "ECU INIT FAILED - check cable/restart" as the error message. I am not tech savvy at all so this has gotten me stumped as well. I couldve sworn I had it working at some point but idk, it definitely is not working now lol.

It feels like eternity since I toyed with any of this so I am sort of needing to refresh myself on anything. Any assistance is as always, greatly appreciated.

freezer

In the logger, you don't need to be on a COM port, and your PASSTHRU device should also not show up on the COM port. Turn on the debugging level to "detailed", should see text similar to this if it is working:

freakyvq

Hey guys, maybe it's off-topic but I am curious if some of you added logging parameters and/or scalings in logger.xml for RR ? if so please share , thank you