Those are all good points that I have considered and here are my thoughts on thoose points.
I originally began with the ANTT bin with the BPC altered for the engine size just to start the car and drive it in and out of the shop. The engine appeared to run so well on short trips that I decided to just stick with what I had and tune from there. Once I had the car ready to go back on the road I started noticing the little bugs and started tuning from there. I knew that the vortec heads were very "picky" when it comes to the timing so I tried to stay conservative with the timing. I had been searching for tunes for a vortec-headed tbi setup and only found a couple. Once I looked at a few spark tables I only became more confused because the tables I could find had way more advance than what I was running. I had always read that the combustion chamber design on vortec heads was very efficient and thus did not "like" as much advance as a typical small block head.The biggest obstacle I ran into was that I could not find any tunes for a '746 ecm and $61 mask. I did view all of the tunes that I downloaded with the appropriate xdf, but found a lot of figures very different than any of the $61 bins. Anyhow, back to the point, I did eventually find more tunes for a vortec-headed tbi setup and used them by copying and pasting and then shifting the entire tables to more closely resemble the $61 applications. I only recently began using the timing tables that I borrowed from and the problem is that the engine runs a lot better and really came alive, but then I started encountering issues with the spark plugs appearing blistered and a true misfire began appearing. It was at this point that I finally stumbled across the info regarding knock sensors and ESC modules and them being specific to a particular bore size. Once I change over to the correct ESC module and knock sensor I should be able to adjust the spark tables more accurately and much faster.
I have done a lot of reading the last couple years on TBI injectors regarding flow rates and fuel pressuress etc...... I am aware that as fuel pressure increases the injectors become more erratic and can also behave in an unpredictable manner or malfunction. I haven't really ever been concerned about the injectors only because I never encountered any known issues in the last 3 years. And from what I have read TBI injectors usually can handle increased pressures up to ~40psi before they begin to have problems operating properly.
Dumping the 160 degree thermostat was definitely in the plans for the near future as I had noticed that the engine ran very cool and it just wasn't necessary.
The problem I had with lean readings was that, for the most part, the ecm would see the lean reading and would take a very long time to alter the INT and BLM values as if there were some sort of malfunction. I also noticed that when cruising the engine would surge and the surge exactly matched the switching of the o2 sensor as observed with my dash mounted gauge.
I am definitely in agreement with the limitations imposed by the current exhaust configuration. I would have preferred to install the engine with a good set of headers, but I was on a very limited budget. Some of the soggy feel on the top end can be eliminated when I happen to stumble upon a good timing and AFR combination.
I totally understand and agree with that statement. I mainly wanted to get a dialogue started in anticipation of slower and fewer responses as that's what I am used to. I have barely scratched the surface regarding what I know and don't know about ECM tuning and the thought process that has led up to this point. I had also anticipated having time to upload a couple of my latest tunes and logs already, but my schedule is just too busy and unpredictable. I haven't had the time to get on the laptop that I use for tuning in the last few days to upload some tunes and logs. I have 3 laptops and one of them is dedicated to all of my tuning and logging which is why I have been able to hop online and post, but not upload something for youguys to look over. I will be driving my car a bit today so I will try my latest tune and log the drives and upload them once I get back home.
Thanks for your time and input,
Phil
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