yeah I had my tune laptop stuck in another vehicle. here are a couple runs with minor adjustments to spark and lowering the VE a bit more.
yeah I had my tune laptop stuck in another vehicle. here are a couple runs with minor adjustments to spark and lowering the VE a bit more.
Screenshot 2025-05-22 220940.png
This area? I should go up so it expects more air? What does this table tell the ECM? The g/s of air to expect past the MAF?
I doubt that cam has less VE at WOT at lower rpm than it did. Certainly by ~2,000 rpm it is moving more airflow. I have tuned a bunch of cams similar to that one in multiple engine familes. The added overlap will typically make it move more airflow at WOT. Getting out of the GM world, I often find increased VE and torque adding overlap via tuning on DOHC engines either advancing the intake cam or even retarding the exhaust cams compared to stock. Same exact cam, different timing events, adds power everywhere in the curve and ironically the biggest gains from that added overlap are at lower engine speeds. Compared to the emissions friendlier wide LSA stock stuff, more overlap equals higher VE and more torque at WOT. In an extreme case of cam events adding overlap altering power curve, I saw a Nissan 3.5L HR engine gain 37.9 rwtq at 2,500 rpm at WOT merely altering the camshaft position tables. That 3.5L wanted a lot more overlap to perform at lower engine speeds. It is not uncommon to gain 50+ ft/lbs on a LS V8 when you go away from the stock 116 LSA cam.Originally Posted by blindsquirrel
Last edited by Fast4.7; 05-23-2025 at 04:18 PM.
That is really good information to digest and consider as I also expected to go up in my VE table shortly above ~1500RPM and be pretty steep from there up to around 5-5500 RPM where it will curve off the Torque curve and lower VE table values exist there after to red line.
I have a couple of 100% TPS runs in those two log files but it shows I only got to around 5K RPM and it shifted I guess, I was watching where I was going. So I know I probably have some work in the 4L60E to tune as well now but wonder if I need to wait until the clutches and torque converter seat fully before giving these full send runs and closing this out. Ive always waited until around 250miles before I get to romping on anything newly rebuilt.
I believe my confusion with previous questioning was that MAP is related to VE, not MAF variables, right? What we have noticed over the past week since doing some more tuning is the suv drives ok, it runs better when it gets to temps and at highway speeds. I notice the logs show constant 30% add to the stft (havent re-enabled ltft yet). I know there is VE tune then MAF tune but I guess I'm missing the jump between the two and what variables (tables) i'm looking for in those situations. I've read about the Hz and g/s relation in the MAF vs Freq table but all pointers are "decrease up to 1700Hz by -5" and go from there. I'm not following that logic or the jump between 1700 and 1900 being that drastic. The air intake just made my tune worse ( as I expected but owners know best ) so now that is throwing off the MAF Calibration I suspect or I didnt hit something along the line with the upgrade to 50lb/hr injectors. I did add all the data to the injector table for the correct setup as seen in the config above. The AFR commanded is 13.4 at throttle most times but owner reports it is usually reporting 14.6 - 15.3 most times on the wideband gauge. Not sure my spark settings are correct either. Reverse doesn't stall anymore after decreasing the VE 2% across the table. I need to go back and add to the upper rpm tables I suspect though now. Do I need to mess with the power enrich at all or throttle cracker, DFCO, airflow decay, airflow initial, throttle follower, spark base corrections, idle spark advance? I am watching the monitoring but not sure what I'm looking for as tell tell signs outside of the stft and the MAF SAE vs Dynamic Airflow reading. MAF vs Dynamic Airflow is close but MAF reports 3g/s more most times. Does this point to needing more calibration adjustment to the MAF Calibration or is my VE table off still? My understanding of the VE table adjustments are that at idle it should be small values and larger values above 2K rpms up to 6K rpms then drop off slightly. My config shows that but still lean conditions. I did install a high flow FPR from Deatschwerks 6-M02-4 to see if it helped with fuel flow but I dont suspect the fuel pump or injectors to be the issue now but rather the tune as I see rich conditions at times depending on the rpm range. The PCM is adding fuel as it should but not until the STFT picks up on the lean state at startup, which is usually taking 5 minutes of idling, then some magical table kicks in and off we go like nothing happened. Honestly the tune runs like shit, lol. All this gear should make this run better than when the owner brought it to me but the tune seems to be holding back the hardware. Might be outsourcing at this point as the owner wants the vehicle running and I don't blame him. Luckily it was a favor from me, not part of the deal. It's been quite the learning experience but I'm still weeks out at this speed from getting a working tune without some breakthrough moment from you great guidance and resources. Going to go back and re-read the sticky for before you post warning banner with the info on MAF vs VE tuning steps and look over others doing those steps best I can find. Thanks for the comments and guidance from yall!!
1st VE table / open loop tuning
2nd MAF / closed loop tuning (havent done yet)
3rd transmission tuning? (havent done yet)
5th_try_1.hpl2001 GMC Yukon XL_5th_try_VEDraw_50LB_blend_ALL_MIXED.hpt
Could someone look this log over and see if that is looking better? I feel a better response out of the motor now, better pulls, smoother. AFR observations from the WB are showing pretty constant 14.6 AFR dipping to 11.5 at WOT through the RPM range (I assume that is PE kicking in) and bouncing to 15.5 occasionally on initial throttle crack. On throttle let off it goes to 13.2 coasting at 1100 RPMs doing ~50-60 mph. The torque converter is a 2200-2600 RPM lockup TC (any concerns there?) pretty smooth shifting out of the new transmission putting around town but kinda stiff at load or WOT. It does seem to want to creep off idle more aggressively now but is that just due to the higher idle speed? I may knock that down 50RPM and see how it runs. I did play with the MAF calibration some and that seems to have helped but still figuring that part out along with spark and what to look out for in the monitoring. Thanks for the motivational words. Had to step away from this and come back with a fresh look. My VE table was so far off after looking at readings and adjusting some. That really is the key to getting this in the ballpark. I have the new AEM 340LPH fuel pump now and will install it next week. SUV is running good thus far but I have not pressure tested yet. There still feels like some room for improvement as it isnt 100% smooth through the RPM range and has some points you can feel it pulling and others it seems to bog through. With this new tune and TC/cam, are there rev limiters and adjustments to shift points I need to move so it is doing so at better times in the range? Other transmission adjustments recommended? I've usually seen people leave torque management alone but I need to read more up on the tuning portion of the 4L60 with this new configuration.
Additionally, What monitoring layout/field am I looking for when reading NBO2? All I see is the mV readings bouncing everywhere. commanded vs AEM WB AFR is within +/- 1 most times. Going to hookup the AEM to monitoring today so I can overlay them.
Is the PE engaged at either MAP @85KPa OR TPS @80% in my config layout? My MAP never gets to 80KPa so I wonder where to go with this section. I understand it is just used to richen up the upper RPMs or at WOT but wonder if it is an Either OR statement or BOTH have to apply to enable.
Last edited by COmountainman88; 05-31-2025 at 07:41 PM. Reason: missed question
bueller?
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