Quote:
|
Originally Posted by f5fstop
You say one affects long term engine durability, and the other flaw you don't mention. Just curious, what are these flaws and how does one affect long term engine durability?
If these are legitimate, I have no problems confronting Johnny boy, one of the programmers. I do know there had to be different programming parameters for the H3 engine, even if it is used as an optional engine on the C/C trucks.
But I would also be curious to know how your program would be any better, and what long term durability tests you have done. I do know that there are some H3 EX VIN production vehicles running around with over 100K-125K and only problem with one of them was a replaced cylinder head, an issue well known to most of us here on the Forum. (Sorry guys, the ones I have seen have not made the trip outwest to test long term driveline durability; these are engine/trans long term test vehicles. The driveline ones are in Mesa - where I would love to be - or Kapuskasing, Canada - where I would hate to be.)
If, as you say there are flaws, I'm sure the programming people would be very interested in the data that shows the flaws.
As for a dealer knowing if there is a reprogram to the vehicle. I agree, only the top 5 percent of tech would ever know a non-factory program was on the vehicle, and then only if they actually took the time to sit down and think, and even most regional service engineers would not notice the fact if called in for an engine controls problem.
Is it possible to re-flash to the original program if necessary, and then re-flash back to the custom program?
|
It is possble to reflash to the original programming. You can either write the calibration data only or flash the entire operating system (for using a PCM for another vehicle). Reflashing the calibration data only takes about 40 seconds.
I start be reading in the existing PCM's program, tweaking the tables, then rewriting the new calibration data.
I am in the early stages of evaluating someone else's tune. I want to see if they find these "flaws". Actually, another channel is open with GM to discuss this along with new auto tranny shift speed trajectories to improve MPG, high octane and low octane timing tables, ECT and IAT timing adders.
The durability issues surfaces with a certain type of driver. Someone tried this "flaw" to intentionally limit power on the dragstrip to limit their ET to meet NHRA rules for their LS1 ragtop. This flaw forced the engine to operate in region where it shouldn't have. I know that H3's aren't for the dragstrip, but this was a real-life example of what could happen.
I haven't done any durability tests. I have never ever seen anyone do this in a program before. For an extreme example, if I told you that I am going to run a 20:1 air fuel ratio, do you really have to run a long term test to judge the durability versus a 14.7:1 A/F engine?