current setup is:
LQ4 lower end with trickflow GenX220 Heads, Cam 228/234 @.050 lift .609, headers, 36lb injectors with factory TB and LS6 intake.
Idle seems off even for the cam and it smells really rich.
I have my tune and logs. I would really really appreciate it if someone took at look and provided me feedback.
There is no guessing with this stuff, it's either right or it's wrong.
Your log shows that the fuel trims are pulling fuel, so yes it's rich. You must purchase a wideband o2 sensor so you can monitor real time air fuel ratio. Then that wideband must be included in your logs so you can properly fix the airflow model.
The log shows that it's running without a MAF sensor, so you'd only be tuning the VE table with your wideband to correct the fueling.
I can't view the file right now to check if the settings for speed density are correct or if you have the proper injector data but those 2 things need to be correct.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
o2 sensors can mislead you for idle with a decent camshaft, use a wideband to confirm your fueling. looking at your idle values in the VE around the idle area 800rpm and 50 KPA they are 15-25% bigger than I would have guessed would be there with that size camshaft
Is this a Return less fuel system?
and did you change the flow rate VS. KPA table under fuel >general > flow rate?
the table looks like a return less system where the fuel pressure is controlled by the fuel pump Via the PCM. (probably a better way to describe it but I can't think of it right now)
ok your VE table is spraying Way more fuel then even my stock engine and you have way bigger injectors. you have some of the data telling it to work 110% of the time
I can only suggest what I found saved me a lot of headaches with my car with idle, but others may say it wasn't a good move as it could be washing any oil off my cylinder walls due to injecting fuel too late and having it pooling in the cylinder rather than atomising with the incoming air while the intake valves are open.
In VCM Editor under Fuel, General, Injection Timing, Boundary/Normal/Makeup, I took Boundary out to 8 and then varied the Normal and Makeup tables to suit what felt the best in my car. These are the values I used for each table:
Normal:
ECT -40 to 20 = 3.63
ECT 32 = 5.00
ECT 44 to 56 = 6.15
ECT 68 = 7.14
ECT 90 to 104 = 7.90
ECT 116 to 140 = 7.14
Makeup:
ECT -40 to 56 = 6.54
ECT 68 = 7.00
ECT 80 to 104 = 7.50
ECT 116 to 140 = 6.54
Until I changed this, I was running in PE mode from 0-1200RPM and commanding a AFR of around 13.2 just to get it to idle reasonable. I don't have a massive cam, it's something like 224/224 or 224/229 from memory. Basically, with my injection timing boundary set to stock of 4, I was guessing that unburnt fuel was being sucked straight out the exhaust while both intake and exhaust valves were open during the overlap. This excess of unburnt fuel gives the rich smell at idle. It also must trick the computer into thinking it has delivered the correct amount of fuel as commanded, but without it all staying in the cylinder to be burnt then the engine isn't making as much power as it should. Initially commanding my engine to be running at 13.2AFR still would have had excess fuel going into the exhaust, but it then would have had enough fuel getting delivered into the cylinder to allow it to run a lot smoother. Once I changed the injection timing I have been able to let it run back in non PE mode at stoich of 14.63.
I still get a pretty rich running smell at idle, but it has been heaps better since doing this. I also still have an idle that still needs a fair bit of work to get nice, but at least it's not pumping massive amounts of fuel in just to keep it running!
I hope all that makes sense and helps out a bit. I couldn't find much information on the Injection timing normal and makeup fields, nor have I run a Wideband on my car after all this time, but it's been running this way for 2-3 years and I haven't noticed any issues yet. Mind you, I haven't taken a head off to check out the condition of the cylinder walls!
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