Nistune Forums

This is a copy paste from what I posted on the Nicoclub forums, but I must say I'm very happy with how my car is behaving, after all the learning I've manage with the whole Nistune experience.
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I was able to race my CA18DET on the weekend and it didn't blow up! :gapteeth: :biggrin: haha!

Jokes aside, the Nistune powered CA18DET 200SX is responding pretty good to my cautious tuning attempts. I was able to run 3 all out drag races, up to 7000rpms @14psi, drive back and forth almost 100 miles to the race track, without a single hiccup.

Had not raced it since 2010, but I had a blast. It was an unofficial Drag War, so no official times were given, but I raced against a couple of cars who are usually in the 14secs range, so I'm pretty sure I'm close to that, specially with my old street tires. My wife also participated with her car, which she enjoyed a lot, racing more than 6 times. :rotfl

Here is a video, S13 vs Integra, and some pictures (me and my wife):

http://www.youtube.com/watch?v=iwmhB6VgJSw

Drag Wars feb 28 2015 by CamsX200, on Flickr

Drag Wars feb 28 2015 by CamsX200, on Flickr

Drag Wars feb 28 2015 by CamsX200, on Flickr

Drag Wars feb 28 2015 by CamsX200, on Flickr

Drag Wars feb 28 2015 by CamsX200, on Flickr


Now back to the actual tune, I flattened the boost range up top, yet I still have to resolve the boost leak issues, and I think I'm also suffering from air reversion towards the Z32 MAF (due to the recirculated BOV). More testing to be done soon.

Driveability wise, Im very happy overall:
idle - 14.6 to 15.1 afrs
cruise 3k rpms - 15.5 to 14.7 afrs
0 to 2 psi boost - 14.0 to 13.7 afrs
14 psi boost - 11.4 to 10.7 afrs (dependent on boost leak :frown: )

Nistune 009 New Fuel Map by CamsX200, on Flickr

Hi guys, me again. I sorted out 2 major leaks, on the TB and the BOV, and now the car is spot on with my current MAP/Kconst on WOT above 3500rpms.

I would like to work into improving the driveability on low rpms, cruise and Tip In next.

@Matt,Buddyworm: I've been reading about the CA18DET injection switch from sequential to batch (which I wasn't aware off until recently), and I would like to smooth out this transition. Any recommendations? If you see my log, the injection time is increasing up until 9.43ms, but the other threads I read state that the injection switch occurs around 7.5ms of injection time, right? My engine has a 4 ports head, so I have no use for the "Variable Intake Solenoid" table, I guess. Could this table have anything to do with the injection time behavior? How do I disable it altogether?

@Louiswun: I'm definitely suffering from air reversion on my Z32 MAF because of the BOV valve recirculation. Do you have any recommendations in order to minimize/eliminate this problem? The recirculation plug on my Intake Pipe is perpendicular, so I was thinking about changing the angle a bit towards the turbo, but I'm not sure if this would help.

Nistune 010 by CamsX200, on Flickr

Cheers!

@Matt,Buddyworm: I've been reading about the CA18DET injection switch from sequential to batch (which I wasn't aware off until recently), and I would like to smooth out this transition. Any recommendations? If you see my log, the injection time is increasing up until 9.43ms, but the other threads I read state that the injection switch occurs around 7.5ms of injection time, right? My engine has a 4 ports head, so I have no use for the "Variable Intake Solenoid" table, I guess. Could this table have anything to do with the injection time behavior? How do I disable it altogether?

Its one of those standard things with the CA18DET ECU where it does a switch over at a certain point. Most users report about 7.5ms but this isnt an actual definate number. Let me look into it tomorrow and see if I can finally track this down, since I have the CA18 code disassembly in a better state than previously

CamsX wrote:
@Louiswun: I'm definitely suffering from air reversion on my Z32 MAF because of the BOV valve recirculation. Do you have any recommendations in order to minimize/eliminate this problem? The recirculation plug on my Intake Pipe is perpendicular, so I was thinking about changing the angle a bit towards the turbo, but I'm not sure if this would help.

maybe this can help

viewtopic.php?f=11&t=1879&start=15

Interesting solution with the bent pipe. I don't know if should just vent to atmosphere (cold pipe BOV) and get rid of the recirculation, or if it would cause any other weird issues that I haven't experienced.

Matt, were you able to look at the Solenoid code bit?

I'm not sure how to improve the off boost area of my map. I'm very lean on low rpms from Stop, and very rich on the tip in / low boost transition / injection mode change area. Also somewhat lean on Cold starts. Could any of this be improved with any of the Crank Enrichment tables?

I mean, car is perfectly driveable, but I keep thinking it could be better. Maybe more timing down low?

@Louiswun: I'm definitely suffering from air reversion on my Z32 MAF because of the BOV valve recirculation. Do you have any recommendations in order to minimize/eliminate this problem? The recirculation plug on my Intake Pipe is perpendicular, so I was thinking about changing the angle a bit towards the turbo, but I'm not sure if this would help.

Definitely change the recirc to point away from the MAF. I had this problem with my R34 when I purcahsed it. We had to cut the pipe and reweld at an angle then it fixed it

Sorry forgot to look into that. Got distracted

Matt any news?

I'm still having a hard time controlling the injectors changeover from Sequential to Batch fire on Boost transition. Injection time in sequential mode keeps increasing which pushes AFRs to 11-10.5~ in areas were it is supposed to be around 13-12.5~, until it switches to Batch fire and AFRs allign perfectly with the Fuel Map from there on. The injection changeover should be around 3800rpm (according to Wiki), but I'm not sure if it is also LOAD dependent or if perhaps Injector Latency is still too high. I see it happen all over the place, from 3400rpm up to 4500rpm. Any ideas?

Current map:
Nistune 014 by CamsX200, on Flickr

2nd gear pull:
Nistune Rich AFR 8.06ms Injection by CamsX200, on Flickr
Nistune Correct AFR 6.88ms Injection by CamsX200, on Flickr

4th gear pull:
Nistune Rich AFR 8.73ms Injection by CamsX200, on Flickr
Nistune Correct AFR 6.98ms Injection by CamsX200, on Flickr

Another 4th gear pull:
Nistune Rich AFR 5.61ms Injection by CamsX200, on Flickr
Nistune Correct AFR 7.01ms Injection by CamsX200, on Flickr

Cheers!

Sorry still looking into the code on this one

i don't understand your problem
your AFR are ok
real AFR will never match this from map
you can put 10 in map and have 12 real AFR, this is normal

I know they are OK. It is more like a small annoyance.

I've managed to set my Kconstant very accurately, allowing me to control on Boost AFRs the way I want them, and however I change the values on the Fuel map is going to be somewhat correlated to the real life numbers I'll be seeing.

The ignition map is moving smoothly as it transitions on WOT.

I just "want" to achieve a similar smooth transition on my Fuel Map, but I don't standard how or if I would be able to achieve it. YES, I'm that stubborn.

My list of unknowns and/or incorrectly set, possibly related, goes with:
- wrong latency
- lack of Intake Manifold Secondary Butterflies
- lack of 02 Sensor
- inconsistent injector changeover
- many other tables and flags I still haven't messed with

Have you tried to set values in your fuel map to read correctly on the wideband at this point? If you are able to move the switching point to a different RPM/TP it will means the same issue but at a different location

Trying to get AFRs on the map to meet the wideband probably will not happen due to different injector batching may cause different AFRs which will never match the 'theoretical' numbers because of the double injection time used per cylinder when it changes to dual batch when it halves

Other tables wont necessarily help you here

Yeah, I was thinking about it last night. Will give it a go and report back. Since it isn't the full boost area there shouldn't be any major risk in tweaking the values mid-range.