Ive had a lot of experience in trying to make the stock ecu happy under boost. A reflashed ecu should already be happy but unless it was tuned on your car its a crap shoot. Im guessing NGM tuned the ecu to go into open loop as soon as it sees a maf voltage that correlates to a flow value equal to zero psi. I bet he did this so the ecu switches to less agressive timing maps as well as stops the ecu from trying to reach stoich afr. Throw in meth injection that is not ecu controlled and your afr control is garbage. Meth is also a band aid for a ineffective cooling system.
The J&S system is decent but designed for older ecus with sluggish knock retard. I have a feeling NGM didn't mess with optimizing timing and knock sensitivity so his solution was use the safe guard. Does the safeguard rely on its own knock sensors?
Yes the J&S has its own KS. I had a long talk with the guy who engineered them once. When it's set up properly, it'll pull timing on individual cylinders when it senses light knock, then put it back once it goes away. It's not supposed cost any power. That's the function I'll utilize. I also have the dash mounted display which is really nice.
So as it stands right now, I'm dumping fuel on tip in, the WOT AFR is in the 10s up til around 5k, it leans to about 12.2, then dips back down to 10.2 at 7,000. So, it's costing me some power, but it's not as lean as I previously thought.
My after cooler is totally overbuilt, and my upper IM stays just warm to the touch even after multiple pulls, so I'm good there.
I tried a little datalogging today. My fuel trims are all over the place, and the ECU does not behave how I expect it to. I suspect that's due to the goofed up tune, and it probably won't be cleaned up with a piggyback tuner.
Do you know of anyone in my region doing custom reflashes on these? The local Hyundai club has a guy come out who does ECU tuning, but he doesn't do GKs.
Otherwise, it's looking like a standalone is in order.