KAMRF Variances Bank1 vs. Bank2 (Intro/Long Post)

[decipha]

the perload histogram just logs perload and throttle position

perload itself is the error percentage since it should be 1.00 at wot. Thus if its only .88 then you multiply the load in fn035 at that rpm by .88 and presto.

No, you can ignore load for perload, best to use actual perload for the correction as described above.

Yeah with the sc restriction about .7 at wot is perfectly fine.
With the sc flowing that should go to about .95

[Coz_KB95]

Ok, onto the next challenge. Having a bit of a struggle getting Idle Air Dialed in and I had imagined that this would have been the "Easy Part".

Using the 'Arbitrary Values Option' and I get the impression from the behavior of the engine is a bit erratic, its stalling on clutch in coming to a stop. I've smoke tested and can't locate any leaks so I started thinking about something and hoping someone would be able to confirm my logic or slap me out of this unnecessary analysis cycle I'm looping through.

Here goes: While I'm running CBAZA and T4M2 as the base tune and strategy ... I've converted the intake tract to the GT40 Lower and use the Fox-Style TB, TB Cable and of course a Fox style IAC Valve.

Now ... for the GT40/Cobra Lower intake, I had a look in the stock J4J1 ISCTransfer and there are definitely differences between ISC Duty Cycle and Flowrates in FN8000 between J4J1 and T4M2. Now ... with my throttle plate set at what I think is the minimum the car will idle ... and a DSDRPM of 672 ... ISCDuty checks in at .15 steady (because it is up against the min ISC airflow clip). In the T4M2 ISC transfer, that translates into 0.120 lb/min. If I look at the J4J1 ISC Transfer 0.120 lb/min checks in at ~.35, if my interpolations/flow calculations are correct and I believe they are.

To Compound all of this ... I had a look in the A9L2 base tune ISC transfer where .120LB/Min checks in at .28 ISCDuty.

So ... my questions are, which ISCDuty value/transfer is correct and would I be able to port it over? My assumption is that the transfer from A9L2 should be most accurate as the Valve I'm using is a Fox valve. What else would need to change in T4M2 in order to port over the the values in FN800/8000 from A9L2? Am I completely going about this in the wrong way and ultimately the duty cycle doesn't matter?

Thanks in advance ...

[Coz_KB95]

I have been wondering ... as it pertains to understanding what's happening with fueling bank1 vs bank2. I noticed that when I set numego = 1 and assign both banks to Hego1 ... Hego2 stops switching. Just want to confirm that is not a function or result of setting Numego =1 and means that bank is actually camped out rich. Or is it just not switching because it is disabled? If that is the case, any harm in leaving Numego = 2 and assigning both banks to Hego1 so that I can keep an eye on the switching behavior on bank #2?

[decipha]

no its not

if its reporting rich then its camped out rich or shorted

harm is up to you. leave it set to 2 hegos and set all the ports to bank 2 instead.

[Coz_KB95]

Yep ... tried to leave is set to 2 and all ports to bank 2, she didn't seem to like it. I went in a bit of a different direction after some reading. I figure that either the scavenging from the x-pipe ... or the longtube headers and the effect on the Hego's at idle ... either or both had me fighting her for a smooth and stable idle. So ... I decided to flip her to OL at idle.

Night and Day difference, idle calmed right down and overall manners returning to idle and off throttle clutch in are much much better. I did quite a bit or driving and only had 1 instance where she stalled coasting to a stop. Still a bit of fine tuning to do with ISC and DESMAF, I think that is likely where the issue is. I had a chance to do a few WOT runs with the blower bypassed, checked my PERLOAD adjustments and they look pretty good. Only a few RPM ranges that are outside of +/- 5% of 100 PERLOAD. Confirmed that the LAMBSES I'm demanding based on PERLOAD are coming in and my WB is following suit.

I'm just pouring over some logs ... but feel like i've learned so much in the last few days, and made progress, which is pretty satisfying. I was looking for some second opinions on fueling corrections and where I may be battling the injector breakpoint (which is a concept I'm not completely understanding just yet). I will post up some histograms along with my log and tunefile. Would appreciate your and any other opinions on further fueling changes.

Thanks again for the quick answers and guidance ... incredibly helpful!

[Coz_KB95]

Trying to finalize the dial-in of the MAF before I finish up with startup-enrichment and finally fine tuning Idle-Air. From the previous post, I now have her idling in OL and took her out for a few runs last night so see where things net out with fuel corrections. I'm using the Fuel Error from Bank1 and comparing it with the Fueling Error from my WBo2 which is sitting in Bank2. Here's the picture I'm getting on corrections:

So, plain to see that Bank2 is running a bit more rich than Bank1, I'm less concerned with the closed throttle figures. I'm more focused on part throttle and what seems to be happening from IMAF 200 - 225. Wondering if that might be the transition through breakpoint that is leaning Bank1 a bit, and requesting more fuel which is in turn richening up Bank2. Everywhere else in part throttle I'm within 3-4% which I think is acceptable.

Breakpoint for the 42lb green-tops is the value from the Injector data on the site, unchanged at 0.00002119.

Posting up the tune file and the last log with those numbers. Welcome everyone's thoughts and suggestions.

Thanks!

KB-95_9_28_2025_DriveLog.xdl

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~KB-95~T4M2_09_28_2025_v3.3.bin

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