Corrected Deadtimes still rich on lowest manifold pressure

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forevertrj
Posts: 135
Joined: Mon May 12, 2014 4:13 pm
Location: Victoria BC
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Corrected Deadtimes still rich on lowest manifold pressure

Post by forevertrj »

Alright so!, I have a
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Fuel Injector clinic 1000cc/min Injectors (i have them set to 858cc/min @ 39PSI fuel rail)
AEM high flow fuel rail.
AEM adjustable 1:1 FPR.
Walbro 255 Fuel Pump.
Hondata s300 v3(bluetooth).
garrett GT3076R dual ball bearing turbo.
b16A JDM motor/block.
stock bottom end, and GSR Cams.
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Idle set screw has been tweaked all the way to one side to get the idle to drop, when I unplugged the IACV(idle control valve) and the RPM's drop to 550, not 450 like advised by the help file, with the duty cycle at normal position in the idle tab, I've got the blue hondata intake gasket, and checked the manifold lines and there aren't any leaks before or after the throttle plate. (i'll be checking the IACV for crud tomorrow as it could be gummed up potentially, but as for the help file it said if you can't get 450 RPM there is a manifold leak, any tricky spaces to look where there might be leaks? any issues with the blue hondata intake gaskets not sealing at all?

THE SETTINGS
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I set the dead times for the fuel injector clinic injectors to the specified values, I'm running my fuel rail PSI at 39psi, which on the baseline data sheet for the injectors are rated at 858cc/min flow rate.

inputed stock injectors at 240cc/min in the calibration and the new size to 858cc/min,
followed a wicked set of instructions for setting dead times since the dead times I was given are giving me too rich* of a condition as my fuel value is set to like 1 with the recommended dead times, you'll see what I mean on my calibration.

Now for the question, I set the dead times to lower then whats recommended to get my -20.5Hg manifold pressure up to a fuel value of ~35 for any Rev's above 1000RPM, and they are a bit lower for my idle, @ 900Rpm. but now while I'm cruising and am at about 1% TPS I'm about 11.5 air fuel ratio's but as soon as I get into the -20Hg of manifold vacuum, it goes back to a perfect 14.4-14.9 air fuel ratio. the question I have is now that I've calculated the dead times (i set all low manifold pressures from 0 - 2000RPM the same fuel value, set idle to about 1500RPM and set the 14.16Volt dead time and then changed fuel when necessary to bring AFR values back to 14.0-14.2, then loaded the car circuitry with my amp/sub/music, headlights, fan, and wiper blades to get the 12.5v deadtime set) I should be able to change the dead time values to an even lower number for 14.16volts to effectively achieve a longer duty cycle but squirt the same amount of fuel as before with a lengthier dead time, or will this in turn create pools of fuel on the valves in the intake runner?

Conclusion!
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everythings set up perfect except -25.9 inch/Hg manifold pressure vs all RPM's. the lowest AFR i can get is 11.9 with a fuel value of 0, which is like 2% duty cycle on the injector there is practically no change.
SO ... should I decrease the dead times once again to effectively raise the duty cycles needed to squirt more fuel once I've reduced the dead times from say 0.87 to 0.77ms as I'm suspecting I'm needing to
or is there a way to add an overall time to the injectors duty cycle or "when" it squirts to how much it squirts to fix the issue, also I can't put in a negative overall trim as there is not enough duty cycle to trim.

also all my adjustments were made after the car had been warmed up, it's set to stock 16 Degrees for timing, and Map/TPS/IAT/ECT/IACV sensors are working great, only discrepancy is that my idle control screw is maxed to the right turn position.

EDIT
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side note, when I had the 14.16V dead time at say 0.6ms the car was stalling at 900RPM, So I raised the idle to 1500rpm and was able to dial in 0.87ms for the dead time, I'll be trying this method again tomorrow as I'm thinking I just needed way more duty cycle(fuel value increase) to compensate, and lowering the dead times to 0.6ms and will set the RPM to 1500 will report my findings if I'm able to add more duty cycle and getting the right amount of fuel for low manifold pressure, any info in the mean time would be great!
Attachments
B16A_GarrettT3076R_FIClinic858ccRail@39PSI_8PSI_LnchL@5K_RevL@8.2K_LwrDedTimesThanSpecSht.skl
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forevertrj
Posts: 135
Joined: Mon May 12, 2014 4:13 pm
Location: Victoria BC
Contact:

Re: Corrected Deadtimes still rich on lowest manifold pressure

Post by forevertrj »

OK SO! I've fixed the issue, I did exactly what I said I would and decreased the dead times slightly, and also another big thing was I set the lowest manifold pressures all to about 12, and increased column 2 to about 60, effectively making idle somewhere around 45-50, instead of making column 1 and column 2 both 45 as a fuel value. I then left the car at 900 RPM, and had it warmed up, turned off all power except the bare minimums, made two dead times close to one another one at 14.16v the other at 14.4v and used these two to get a stable AFR around 14.5, my dead times were approximately .80ms for 14.16v and 0.76 for 14.4v, then turned on all the accessories, windshield wipers, stereo, headlights, and fan with A/C, and then increased the 12.12v value until I got back to 14.5, then removed the 14.4v and set the 16.18v column after taking the calculation of (dead time at 12.11v minus dead time at 14.16v = about 0.53, then took the 14.16v dead time and minused 0.53 to = my 16.18v dead time), I did the same for 10.09v by adding 0.53ms to my 12.12v dead time, then to get the 8 volt dead time I took the value of the 10v dead time multiplied it by 0.50 which gives you 50% of that dead time, and added it to 0.53 (my average change for all other dead times) and then also added the new number to my 10v dead time to give me my 8v dead time. and set my 0 volt dead time to the same as 8 volts.

all said and done, I have to increase my idle fuel values as they leaned out while tuning for some reason, so even though I had the idle at 14.7 before with lower fuel values it's still at 14.7 with the increase from real road conditions, kinda weird but i'm just rolling with it, and no I don't have any fuel compensation if my IAT was making corrections as I changed that to 0, see calibration below for comparisons from my original post to the new one.
Attachments
B16A_GarrettT3076R_FIClinic858ccRail@39PSI_8PSI_LnchL@5K_RevL@8.2K_BestDedTms@1540hrs.skl
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forevertrj
Posts: 135
Joined: Mon May 12, 2014 4:13 pm
Location: Victoria BC
Contact:

Re: Corrected Deadtimes still rich on lowest manifold pressure

Post by forevertrj »

ok so I haven't entirely fixed the issue, but I'm sure I'm on the right track the only discrepancy is the 16v dead time value, once I decrease the 14v value to about 0.5 and adjust the 12v value the average between the two that I need to get to calculate 16v pretty much equals 0.008 or lower, and the calibration doesn't allow any values lower than two decimal places. so I emailed fuel injector clinic and asked them about the 16v dead time and if it needs to be 50% greater or what, I'll post my findings, the only reason I need to decrease dead times still is because at the -23.5" of Hg vacuum, i'm still rich but i'm at about 12.5 - 13.3 instead of a steady 11.0 or even 10 AFR's so we shall see what FIC has to report on the issue and the fact that their data sheet was pretty much wrong by about negative 0.4ms @ 14v, and about negative 0.2- 0.3ms for 12v. so if the recommended from FIC was 1.12ms at 12v mines set to about 0.9ms, and my 14v suggested is 0.8ms but the calibration is set to about 0.66 ms
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