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E67 crate LS3 idle issues
I have here a LS3 "hotcam" crate engine in '60 Impala. It has been running fine for years with the tune that was with the car originally. Now the intake air duct has been modified longer to take air from colder area of the engine bay and I thought the idle problems were due to the MAF being relocated and not dialed in.
I started with dialing in the MAF and noticed than "conveniently" the MAF was already enabled from idle rpm. The dialing in process didn't help me at all. It still has very poor idle and it stalls every time I come to a stop. Then I looked into other idle stuff and noticed many things differing from "VIN-coded LS3". First of all this car thinks it's a manual but it has 4L65 tranny in it which is controlled by a separate box. It seems that everything I touch takes the idle completely away. It just doesn't seem to handle anything below 1000 rpm.
I took off MAF connector and spent few hours dialing in the VVE (there was 30 % fuel trims all over the VVE). I got it sorted or a leap closer to what I wished for but the idle problem is still there.
I tried at least 10 different approaches to timing and idle timing and every time I tried a less agressive timing correction, it doesn't want to run below 1000 rpm at all.
Driver side exhaust sounds like it's leaking right from the seal which is next to the O2 sensor, could that mess this up so badly? I tried to force to open loop on idle too but it didn't do much good.
Could someone share LS3 hotcam E67 file so I could see where the differences are? I enclose here the original tune and a short run with it. Then there is one tune without mAF and longer run with that.