I feel like this is a rare situation that just happens from time to time. As I’ve said before, I know the sound well—cars in the ’80s and ’90s did this regularly on hills because they weren’t smart enough to downshift, even though some of them had knock sensors. The sound I hear is the same one in that Bronco video, and it’s very familiar to me.
The reason I don’t buy into the idea that this will “destroy an engine” is because I hear it in completely stock, unmodified vehicles too. Sometimes it just happens, and we’re simply at the far end of the spectrum now. There are countless daily-driven, boosted cars running the worst 87 octane fuel available and still going 200k miles. Forums tend to over-worry about things that are, honestly, just a thing—have always been a thing, and will continue to be a thing.
We could debate it all day, but I don’t really see the point. When the car lugs briefly, it pings—maybe three or four quick rattles in my case—then it downshifts and corrects itself. It happens fast and resolves on its own. I’m not worried about it, especially since I can intentionally put the car in a situation where it will do it. I’m confident I could make it happen even without a tune.
If we want to talk about real drivetrain stress—tuning, romping on it, drag racing, hard launches from a stop in 4WD—there are plenty of ways to actually beat up a drivetrain. This just isn’t one I’m concerned about. I run 93 octane, change the oil at 50%, and keep it about a half-quart high.
Enjoy the ride, YMMV. This is also why I like sport mode, because it keeps you in a lower OD until you are HWY speeds. That being said, running full Sport mode offers other negatives.
Right, and that was my point earlier. The tune is essentially totally stock in the load range that he's hearing the noise in. The stock tune will do the same thing once kom reaches 1.0 and the load conditions are met.
That doesn't make it right but also it shouldn't really going to have any damaging effects out of boost like that.
One thing I noticed on some of the newer calibrations is Ford got more agressive with their temperature adjustment based on iat and mct. In the winter with the cold iats/mcts it really pushes the timing forward.
So part of the problem can be when you upgraded the intercooler, delete the shutters, and upgrade the intake you are kind of creating a prefect storm of the ecu logic adding to much timing. At a kom of 1 it's going to at a few degrees from the borderline table based on the octane modifier, then it's also going grab a few degrees from the temperature. Of course this is limited by the cylinder pressure tables and a hand full of other tables and ultimately the MBT table its still piling in a bunch of timing. The issues is Ford sized the intercooler, and added the grill shutters to get everything to a specific air temperature and keep it there. So when do all and lower it we end up operating outside of the expected range and having too much timing.
What typically happens in that case, because the knock octane logic learns the octane at low to medium loads it will actually pull back the kom because it sees learned knock but the learned knock is actually because there was so much advance coming from the cold tempatures. The end result is you'll see a log with a KOM of .5 and the logic adding 4 or 5 degrees at WOT once the temps are up in a normal range and then wonder why the kom went down. Well it went down because it doesn't learn octane at wot it learns it at part throttle where the mcts where too cold. The solution there is reducing the ecus timing add at low temperatures and therefore allowing the octane logic to learn and stay at a kom of 1.0 and when you are at wot you'll only see the logic adding 1 or 2 degrees over the baseline timing. At the end of the day you end up with the same amount of timing but you want to have that baseline timing
That's also another aspect of why is a proactive system, it's learning the octane at part throttle it doesn't wait to see knock at wot to pull the boost and timing down.
It's also worth noting that some tuners, especially some of the OTS stuff and even some tuning schools teach you effectively disabled the knock octane logic by maxing out the load limits and removing the spark additions or locking the octane modifier at 0 or 1. That's all bad. Even my octane specific tunes still have the OEM AUTO OCTANE logic built in a safety. My adjustments for boost are only made where the kom of .5 to 1 have an effect. That way if you accidently put 87 in with a 93 tune and your cruise along the kom will drop to 0 and you'll be running the same boost and timing as the stock tune on 87 octane. We call then octane specific tunes because like goose said things can happen quickly and if it didn't have time to learn it might be too much. That's also why our auto octane tunes on. 93 octane don't make the same hp as dedicated 93 tunes. We need to leave more room for error in case someone puts 87 in right after 93 and floors it before cruising and letting it lean we have to make sure the knock logic can still pull enough timing to not cause a problem until the ecu turns it down.
That's also how a bunch of the of the other safeties work. Like the coolant temp, on my tune if the car isn't up temp the kom isn't in effect (making it 0) which means my tunes will only make stock boost until the car is up tempature. Same thing if you a critical dtc like a misfire, that resets the kom to zero and you are right back to stock tune 87 octane levels of boost and timing it's really handy.
I've seen so many tuners that short cut that logic and make octane specific tunes with no ability to turn the boost down or adjust the baseline spark. Just makes no sense to do that, it's built right to the logic just leave it alone.
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