hi! from a newbie in canada. rb25det neo, in 240sx

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polemite
 

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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by polemite »

ok i think i spotted at least one of my issues.
i think i ran through the injector resize more than once, and it looks like each time you do that, it changes the k constant each time, rather than reverting to to original, then writing the new target.

so with that said, which option should i be using when resizing injectors?
k constant
tim/tid
smart adjust <----------*** update: smart adjust is the right answer.

originally i couldn't get smart or tim to work. so i did k. i think that's where i messed it up originally. probably need to reset k, then do smart adjust, right?
injector resize options k const.JPG
(22.61 KiB) Downloaded 1565 times
injector resize options tim.JPG
(24.05 KiB) Downloaded 1565 times
injector resize options smart adjust.JPG
(24.63 KiB) Downloaded 1565 times
Last edited by polemite on Sun Jul 04, 2021 7:55 pm, edited 1 time in total.
polemite
 

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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by polemite »

ok, managed to revert back to an older file, and start over.

My maf cartridge is actually from a rogue, but it’s the same part number as the gtr maf. Not sure if that makes a difference. But it’s in a 3.5” tube with honeycomb straightener. I chose the gtr maf in 3.5 tube (444hp) ****update: wrong choice. this caused me a lot of confusion from this point forward.

k is now at 354
messed around with tim a bit, but realized that's not the right thing to do at idle, so put it back to 512

injector latency was the key that got me started back up again.
found r35 data elsewhere on the forum, and set it for 1780 ***** update: this turned out to be totally wrong. 800us is the correct starting point

afr was really fat at this point. ended up scaling latency back to 1100.

had idle instability when my fans would kick on. adjusted target idle from 550 to 650, and that keeps in running. ****update: this idle issue was cured when i resized the maf to the 621hp version.

afr is slightly rich at idle.

took it for a drive, but i'm alone, so all i could do was log it. on playback the trims look like they are cutting quite a bit. but now i realize, i never reset the trims, and i probably should have.

back at home, shut down and tried to restart, but no go. if i stab the throttle it catches, fires up, and idles. never had to do that before, so i assume something is still a bit off.

here is the log and current file burnt to the ecu.
6 23 test 2_2021-06-23_1540_32.csv
(667.08 KiB) Downloaded 79 times
maf and injector attempt 5.bin
(64 KiB) Downloaded 72 times
Last edited by polemite on Sun Jul 04, 2021 7:59 pm, edited 1 time in total.
polemite
 

Posts: 105
Joined: Wed Jun 26, 2019 10:01 am

Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by polemite »

read a bunch last night, and went out again this morning.

started up fine. so i suspected that the start issues i had yesterday had to do with the crank enrich at warm temps. increasing from 5 to 8 did cure that.


connected the wideband this time, and took a few logs. looks like it's trimming about 10% at low load, low rpm.

just idling and revving in the shop
idle and revs_2021-06-24_1116_07.csv
(81.84 KiB) Downloaded 75 times
drive through the neighborhood and out onto the highway.
drive with wb_2021-06-24_1117_17.csv
(548.37 KiB) Downloaded 69 times
just a short run through the gears, up to 90km/hr
drive with wb 2_2021-06-24_1126_45.csv
(78.58 KiB) Downloaded 66 times
polemite
 

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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by polemite »

oook, after a bunch more reading and wrapping my head around this stuff, i realize it's time to move on to adjusting tim.

looking back on the last logs, i can see the trims at st: -6 and lt -10.
this told me that reducing tim was in order.

reduced tim from 512 to 400, and drove to work.
trims are now at st: 0 to -4, but spending most of the time at 0.
lt: +6.

i find this a bit funny, that st would be going from 0 to cutting a bit, and long term is adding 6%... but it's an improvement, so i think i'm going in the right direction.

i think i'll probably keep trying to balance between getting the latency back closer to 1780 (assuming the 1780 is the correct target**update: it's not), and reducing tim. currently, if i take latency any lower, the idle gets rough, so i assume that i currently don't have much room for adjustment if i need it later. ***update: the rough idle reaction was unrelated to the latency. probably had more to do with the wrong maf selection.

from what i gather, the next step is to also start adjusting the fuel map and load range. for the fuel map, is it really just as easy as selecting similar blocks, and adjusting by the same % as the increased injector % size? reading the documents, it looks like the low load areas of the map don't get touched at all?

*also, should i manually update the maf scale? the drop down menu quotes it at 444hp, which sounds reasonable to me. but nzefi says it can measure 500hp in 3.5" tube. if that's the case, i should be at about 80%...
Last edited by polemite on Sun Jul 04, 2021 8:03 pm, edited 1 time in total.
Matt
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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by Matt »

Sorry I've been away for a few days so just catching up on post here

1. Injectors. if they are unknown then best to flow test them. I've not worked with R35 injectors before so cannot comment here

2. If only idle is lean but mixtures are fine at cruise, then adjust your latency

3. MAF Upgrades. There is 'Z32 load' and then 'max load'. In 90% of cases the Z32 load with lower HP will be fine to use. Otherwise it will bump up to the maximum capacity of the MAF and require large adjustments in load scales/ K constant

Z32 Load is equivalent to using the load range of a 300ZX Z32 MAF

4. If you have 'incomplete' files then maybe your ROM packs are not all installed? Make sure you see Documents/Nistune/ROM Pack/Type34/WC34 RB25 folder. In there should be a 0V81F file. Nistune will sync the maps from the ECU into this file

IF you dont have the ROM pack files there, it will load into an empty file, and then that file only contains maps. It will prompt with warning messages and may cause issues if we add new map definitions in the future
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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by Matt »

5. Injector resize should only be done once (as you found). It adjust the TIM / K constant based on old/new sizes. So keep an eye on this

After resizing, adjust TIM for fueling, and K to load adjust

Use 'smart' adjust since I will look at what MAF you are running and then move K constant back to near factory value firstly, and then adjust the rest of the injector size with TIM

6. Most MAFs with same part # as R35 will work. As long as they are not dirty or counterfeit.

7. Like with my post in the general section, start around 800us for latency

8. Crank tables are adjusted when you resize injectors. They are close, but not perfect. Looks like you have fixed that up okay but increasing. About 8ms crank seems a bit on the high side, so I'm wondering how well those injectors are spraying

9. Okay so you are seeing trims adjusting. So the ECU is trying to target 14.7:1 so see what your trims are like at cruise. If they are near 0 as you do longer trims then it seems close. Maybe pull TIM about 3% lower and that will get the trims almost perfect
polemite
 

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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by polemite »

thanks matt.
sorry for the information overload. in addition to asking all the questions, i've been using this post as an information dump, so i can refer back to it as i go.

the info i got from the tuner about these injectors, is that they are out of a low mileage 2015 gtr. i have no reason to doubt the claim. but what keeps throwing me off about them is the inconsistent, or nonexistent, info about them. next time around, i'm going to try your suggestions on latency and see what happens.

i played around with a few things again this morning. i had some funny afr's (rich) at idle, once fully warm, but that seemed to go away after driving for a bit and stopping again. only change at that point was ambient air was a bit cooler, and i took tim down to 390. my electric fans sure do mess with my idle. i'm running them on a stand alone sensor/relay. i'll try to pay attention to the voltage next time they kick on. ***update: once again, this problem was maf size related.

warm restart was effected again by the change in tim. i didn't spend much time finding the sweet spot, as i was just making stops on my way home from work. so i just bumped it up from 8 to 11, fired up and i left it for now.

cruising afr seemed good, and short term trim seemed to be approaching zero. long term seems to always have something locked in there though. how often does it update itself? do i need to clear it on the fly? difficult to do, as i'm always by myself.

anyhow, i decided to take a stab at a few high load pulls. in the log below, you'll find them at the 44 second mark, and the 3:57 mark. lots of light load cruise in between.

i still have the 4 psi spring in the wg. gonna leave it there until i can figure out what this 38mm gate can actually control on this setup, before i improve the control.

boost starts to creep up fast at 5000rpm, then i max out the tp load at about 12psi/5600rpm. looks like it hit 184 at it's peak. not sure what to expect when i can actually get it to 7000rpm. i'm surprised by the afr's. it actually looks like i need to be adding fuel, rather than taking any out. not sure if this is related to my latency setting, or if adjusting the tim got it that close?

i get a bunch of limit warnings when i replay this log. the load limit is no surprise. neither is the boost limit, as it looks like i need to adjust the bov a bit more. but the speed limit confuses me, as i raised that to the max.

i also get a neutral switch constantly on warning whenever i first log on. is there something i should address there?
maf and injector attempt 5.bin
(64 KiB) Downloaded 64 times
home from work 1_2021-06-27_0659_49.csv
(1.06 MiB) Downloaded 63 times
Last edited by polemite on Sun Jul 04, 2021 8:05 pm, edited 1 time in total.
polemite
 

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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by polemite »

did a bit more testing tonight.

started out with
latency 800us ***update: this is the correct starting point for r35gtr injectors.
k reduced from 354(calculated by injector resize), to 348 (this was actually the oem value)
returned tim from 390, back up to 512

cold start didn't want to catch, but it fired with a throttle blip. from there, the idle was great!!

out on the highway, low load trims were near perfect.

took a high load run, which went kind of like before- load runs up to about 184 @ about 6400rpm.

now, if i'm reading you and the documentation right, this is where i need to adjust k, to reduce that peak load, and keep it operating inside the factory scale.
however, i had no idea which way to go, or how much to adjust it. so i tried going from 348 to 338, and took tim up to 521. ***update: reducing k brings the load scale down. i just didn't move it far enough to make a noticeable difference. tim up adds fuel, tim down reduces fuel. there is a tickbox that will automatically adjust tim along with adjustments to k.

trims were not as good as before, but not terrible, so i took another high load run. once again, off the load scale. so i either didn't adjust it enough, or i went in the wrong direction, or i shouldn't be touching k at all. i'm not sure.

replaying my logs, i hit the speed and tp limiter. not sure why it flags a speed limiter, since i've adjusted these already. and i assume the tp limiter is just letting me know that i've run off the scale (on the fuel map at least. the timing map seems to go much higher).

***update: at this point i was actually closing in on making this work. however, backtracking and resizing the maf to 621hp 3.5" tube, has turned out to be much better.
Last edited by polemite on Sun Jul 04, 2021 8:18 pm, edited 2 times in total.
polemite
 

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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by polemite »

well here's some interesting developments

looking around the internet i noticed that denso also makes a 660cc injector.

for the hell of it, i ran it through the injector resize function, and the k value looked about right where i'd want to reduce it to. (305)

so i figured i'd go and see if it would start, and sure enough it did. latency still at 800. i increased tim to 653 and went for a drive.

once again, trims were at or near zero, so what the hell, i held it to the floor. managed to rev right to the limiter, in 2nd gear. oops (7500rpm)

afr on the gauge looked pretty fat. i was seeing 9's and 10's. unfortunately, the afr dropped communication during the run, so i don't know where it was at from 4800rpm on.

reviewing the log, tp reached a max of 145, so 2nd to last column, at 11psi of boost. injector duty cycle was at 104% @ 7000rpm, but i assume it needs a bunch of fuel taken out of the map.
k size testing 660cc.bin
(64 KiB) Downloaded 79 times
1:48 on the time line, if you're interested
map test 660cc_2021-06-29_1514_31.csv
(493.09 KiB) Downloaded 59 times
so up to this point, i figure i'm on the right track. and perhaps these injectors came out of something like a nismo edition gtr with bigger than usual injectors.
but then i get an email back from the shop i bought them from... nope, standard issue gtr. but he says, don't forget to remove the injector resistor pack. i've never seen or heard of it. did i miss a step here guys, or is he thinking of the pre neo engines? ***update: no, the neo does not have an injector resistor pack.
Last edited by polemite on Sun Jul 04, 2021 8:12 pm, edited 1 time in total.
polemite
 

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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by polemite »

today's update:

since it seemed like my load scale and tim was close, i decided to take my first stab at making some fuel map changes.

doing % change while looking at filtered values raised the fuel in the cells i selected. very confusing.

doing % change while looking at raw values lowered the map. since that was the direction i need to go, that's what i stuck with.

since 380cc is 66.667% lower than 570cc, i figured that cutting fuel to 70% would be a safe move. i did 80% in the last column.

almost all raw values went to 128, except for the highest end of the last 3-4 columns. (talk about flattening the map)

but afr's went lean on boost. i let off at 3600rpm, 93tp, 4psi, 14.5afr.

so i guess the % change doesn't work the way i assumed, or it's not working properly, or something...

maybe i'll try to manually enter some filtered values and see where that gets me.
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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by Matt »

I did a check on the % change in raw view
Around 80 values went to around 60 (at 80%)
Around 190 vlaues went to around 150 (at 80%)

Repeat for filtered Repeat but increase 120%
polemite
 

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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by polemite »

Yeah odd. Mine is definitely not working the same way. My little pop up window is also smaller, and doesn’t have the hints to go along with it. Doubt that makes a difference though. Just weird. But manual entry is working. ***update: the +/- keys do work at raising/lowering filtered values. works on individual cells, and entire block selections.
polemite
 

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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by polemite »

ok, back again to update this post after some emails between matt and i.

800us has proven to be the correct starting point for latency. this has been verified in another post in the general section, titled r35 gtr injector latency. (currently adjusted to 870 to correct idle afr)

turns out the 444hp maf selection wasn't the right choice for me. (oem nissan slot maf in a 3.5" tube)

backtracking and using the 621hp option has proven to be much more accurate and functional in combination with using the 570cc injector resize. the auto-generated adjustments put me in the ballpark right away, and scale correctly along with further adjustments.

crank enrichment will need slight adjustment, as it's a little hard to start. but it does fire and run without any input on the pedal. just takes a little longer than normal.

adjusting the fuel map between 3600rpm-6400rpm, and 88-160 load, to 70% of the original figures got me pretty close on the afr's. slightly on the lean side, so i'm adding fuel in small increments. i've also added a bit in a few cells that were previously closed loop. the boost is very low in those regions, but it looked like they could stand to use a bit of fuel. the next test will tell the tale.

ran off the load scale, so i reduced k, with the tickbox for adjusting tim selected, and the adjustment seemed to pair together well. no further adjustment to tim so far.

in the name of safety, i reduced the timing to 95% in the same load range as the fuel adjustments. however, i think it amplifies another problem i'm having- boost spike.
in all my previous testing i was using the 4psi spring in the wg. it would slowly creep up to 11-12 psi and hold there, so i figured that's about the minimum that my wg setup can control. today i upped the springs to 10psi, but now it overshoots to 13.75psi, which is my current boost cut limit. i raised the recover limit to 11.5psi, but not sure if that's a good idea or not.
the right thing to do is improve my control setup. i was going to tee in my manual boost controller to the top port on the wg, but i think i accidentally destroyed it when taking it apart to look at it's guts. stripped some threads, and now it wont go back together. of course it's some oddball metric fine thread pitch that i don't have in my tap set. 6mmx.75 is my guess.

for now, i'll limit myself to 3/4 throttle. that seemed to work ok in the past for boost control. in the mean time, i'd love to hear some suggestions on just how fancy you guys think i need to get for the boost control setup.
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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by Matt »

There is boost control available for NEO ECUs with Feature Pack 2 firmware
https://www.nistune.com/docs/Nistune%20 ... 20Pack.pdf

I don't normally load it in by default unless requested since it requires rewiring the evap canister solenoid to a boost solenoid (such as a MAC valve)

Firmware is 237x0-0V8xG (FP2) or 237x-0V8xI (FP2.1)

More info
viewtopic.php?f=12&t=2874

I found the issue with the map adjustment is only with NEO ECUs with percent adjustment so have made a fix for the next version
polemite
 

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Re: hi! from a newbie in canada. rb25det neo, in 240sx

Post by polemite »

great news about the boost control!!

unfortunately mine is fp1 though, so i'll have to get it reflashed.

depending on how things go with the current control setup, i might just wait till winter and send it away to whomever has the rom burner up here in canada.

put the 4psi spring back in, and figured out how to get my manual controller back together. i've given it 1 quick test so far. overboosted again, so i'll adjust and try again in the morning.

should i stick with the timing at 95% for now? i know its safer for knock, but it spools up that turbo like crazy.
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