Open Loop EQ Ratio table has increased values from 75kPa and up to mimic PE, but the tables on the actual PE tab are still active. Don't you want the EQ Ratio table to be 1.00 at all operating temps/maps then let PE adjust?
On the EQ Ratio table try making commanded 1.00 for all of 122F to 212F.
Last edited by SiriusC1024; 08-01-2023 at 02:28 AM.
I've never played with those figures (above 75kpa) in the OL table so they're another remnant of the old tune from whichever shop did this back in the day, previous owner. I use the PE values for all my WOT stuff. It's amazing how much i've changed as i've gone along and the benefits found. I'll try that, cheers. Seems an argument with some people saying have the OL table at 1.00 nominal and fine tune in VE and PE, others say make it all 1, tune VE, then go back and fine tune the OL table?
Thing is it's most prevalent at cruise and idle, so 75kpa (idle) down to 35-50 (light throttle). Still wondering if it's not a table referenced from a cold start but not a hot start. I've been browsing the file looking at all the enrichments/delays/decays. Ultimately i want to get closed loop back on the help cover minor variance. I'm also noting the effect of voltage and the role of the offset table as i see around 0.5v swing depending on load.
Last edited by HQforme; 08-02-2023 at 05:30 AM.
Real quick question since I see you're online. What injectors are you running?
I'll look into your issue more thoroughly this evening.
Sorry i missed this at the time mate. I'm running the factory supercharged 6cyl injectors which if i recall are the white Bosch 36 lb/hr 0280155868
I am not at my computer to see file. Are you running blended mode both MAF and VE?
VE only uses the low octane. Burst knock will reduce timing for the quick change of air flow and is what prevents the knock learn factor from bias. If you are running blended mode, log your knock learn Factor channel. GM always wants the high octane table either in mass air flow or in blended mode again ve mode it only looks at low octane. The burst knock will drop the timing for large air mass change, but does not register knock that would reduce in the knock learn Factor. When you get real knock the knock learn Factor starts biasing to the low octane table.
On the left in that tab you'll see a knock ramp rate for how quickly to remove it. Raise it.
Using your Base fuel spark modifier for the fuel/air ratio is good or use a constant conservative spark at the higher rpm and MAP axis but then it suffers when not in PE.
I will look at your EOIT when I get to PC.
As you change your idle timing you are changing your BRA required and idle desired too, so it's very dynamic. You don't want the best vacuum like carburetor. You're not trying to get a signal for fuel. Lower timing and more air flow can be better but it's what she wants and that's what matters.
If Rich, reduce timing and she'll open the TB to get that torque back and lean out. If higher timing then you WILL need to reduce the commanded airflow.
Are you using the DBC or DBW TB? I should wait and look at log/tune file but have to ask.
Do you have the mechanical traction control TB?
To test the desired timing, get up to operating temp and use green button in scanner, Special Functions and you can adjust timing without having to keep writing the tune. Watch how the idle desires moves and what the idle STIT and LTIT is doing.
Let it have time between changes to settle and may even blip throttle 1 time between to allow change to effectively recalculate.
Stay tuned.
I have posted in "ideal idle afr and spark" post a channel list for DBC. If it's DBW I posted that too but it needs refreshing.
Please pray log and tune file with similar titles to keep things straight. Date for a title sucks. Holden Com v1 or something like that is better. With the time difference dates are irrelevant for me.
Cheers!
The last Holden I did was an LSA swap into the club sedan and kept the Gen3 ECM. 952 CHP, it's a Honda Hunter lol.
I look forward to your 11 sec log, please post that.
Here's my suggestion on what the various fuel settings should look like.
- OL table adjusted.
- Injector data from the attached file except for flow rate. 1) Idk exactly your fuel pressure. 2) A little difference here isn't a big deal as long as the VE was tuned for it.
- Transients referenced from a 2001 Camaro (port geometry/surface area), overridden by attached file where applicable.
- Heatsoak enrichment disabled.
From this retune the VE table. It really needs work regardless. Should smooth out a lot and be easier to tune with this fueling info.
Last edited by SiriusC1024; 08-08-2023 at 01:50 AM.
I'll reply soon thanks to you both guys. Been away from the car for a bit.
Thankyou. I've loaned my wideband to a friend who i rebuilt a Dellorto for as part of the service so won't make changes till i get that back.Originally Posted by SiriusC1024
i took the car on a long 3day cruise this weekend and can confirm it's consistent. Once past first start up and into repeated hot starts (cars in convoy stopping, fuel, piss breaks etc) it behaves as expected so it does appear to be some latency in a cold start table decaying to zero, or something to that effect.
Car is speed density O/L. I have both hi and lo octane tables matched, and p/n + in gear tables made equivalent, as was my initial understanding in the first days of trying to learn.
I'll play with the burst knock removal ramp rate. Thankyou.
DBC and i do try balance the base running air with my idle timing and VE adjustments in those cells. I see them interplay without knowing quite the precise link. No TC.
For what it's worth here's the log of my PB. Keep on making those honda eaters mate!
New PB.hpl
Time to drag out a relic!
So the detonation reared its ugly head again. I'm guessing fuel this time. Same tune that i used on my PB pass, same track, similar conditions, no other changes, ran next to a mate with open headers and thought i heard a tinkle over all the noise. Checked the log, detonating the whole bloody pass. The pistons look like the moon and the bores have suffered some scoring. This was 2 weeks before Drag Challenge (our drag week).
Went on DC with timing down to 20degrees total, PE AFR at 12.2, octane booster and she was running clean, only a few tenths down too, high 11.3s. Last day decided to play. 21? fine. 22 degrees? Knocking. Started right off the hit, which it hadn't done before. So i tried something from the very start of this thread, wondering if the light throttle cruise, or the foot brake stall on the line, which calls up mid 30's advance, might be leading to detonation when i stand on it. Cylinder pressure spikes maybe?
Isolated the cells from the foot brake, dropped it to 18 degrees, exact same everything else, not one degree of knock retard. Snuck in 11.29 in the middle of the day with 22 degrees total. Best ever pass is 11.16 with 25degrees on a cool night.
So i'll refresh the motor, new pistons (expensive lesson), leave the dropped timing at launch and get back to chasing a ten.
Funny how the premise i started this thread with turned out to be true, just wasn't actually the main issue. I have learned a hell of a lot!
Logs for comparisonlatest dc tailem final day.hpltailem pb.hpl
Batch of bad gas? That sucks. Life on the edge. Was padding put between the Hi and Lo octane tables after getting Hi spark where you wanted it?
Of course the pistons were damaged from the first round of detonation caused by the oil but i had the tune sorted to the point where it's PB came with mildly pocked pistons. This round did seem to be fuel as it's the only variable. But yes, living on the edge has its risks. As does having high and lo octane matched. No padding. My bad. Again.
Every time we tried to run more sensitive knock retard and lower timing values in lo octane the car fell flat on its face. Even with lower total timing, rich PE etc etc it would log knock and cut the timing even at mid throttle, a point where it really never should. So i'd revert to the old tune, reduce total timing, fatten it up and it wouldn't log knock; albeit with the sensors "softened". Nothing audible either. So the old school belief was "this thing isn't pinging".
With the refresh i'll keep total to 24, race it on octane booster to be safe. Should have no issues. I'd still love to find that middle ground with the knock sensors and burst knock though, for extra safety.
Octane booster like you're saying, race gas, or E85 sounds like the prescription for keeping safe power in your high comp build. Might even consider water meth injection.
Since the heads will be off polish up the chambers. CC them, too. Sometimes there's a lot of variability even on untouched factory heads. The higher the compression ratio, the larger the apparent difference. Could've been the case that timing for good power, that was an average across all cylinders, was too much for the tighter ones. That's one explanation for the fine line on timing between power and not.
I got into the chambers when i built it. A little unshrouding and a light polish. They're 63cc (shaved heads) and fairly consistent, i measured a selection to prove my method. I know i should do them all but i was finding so little variance i just trusted it.
I'm getting a set of spare 241s CNC ported over christmas. As they're not milled at all i may take a touch less off and just ease the comp a tiny bit. They'll flow noticeably better than these hand ported 241s which will more than make up for the poofteenth i lose through a slight comp drop. Or could leave them as is and run a thinner gasket. These current pistons are a few thou above deck so quench is good. New ones will be a few thou shorter in comp height.
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