Stock 392 Hemi Knock Retard

[tbrtuning]

I do not have any experience with Dodge tuning but was just datalogging my personal DD and noticed a decent bit of knock retard. The car is a 392 Hemi Charger and it is stock on a stock tune with torque management disabled. I always run 93 octane by the way.

Is it normal for these cars to have some knock retard or should I be looking for a possible issue with the car or cause of false knock?

stock.hpt
stockWithoutTorqueManagementNoForcedAutostickUpshifts.hpt
16-10-24 11-08-05.hpl

[tbrtuning]

Just went to fix my graph for my log and realized that I didn't even log aircharge to match the graph with the axis in the tune. Sorry about that. I never tune these cars so don't have a config file. I just logged vehicle defaults. Using abolute load in a graph gives you a good idea of what's going on

[tbrtuning]

Just an update for anyone else messing with a 392 for the first time. It appears the knock might have been real. Noise or sensitive sensor calibrations could contribute but a more conservative tune reduced KR so it makes me think it isn't all false at least. I'll be leaving knock sensor calibrations alone for now unless told otherwise from someone experienced. I took out a degree or two of timing a couple places and adjusted commanded lambda and now have the knock retard under control.

It seems like Dodge just tunes these engines very aggressive from the factory. At lower RPMs adding some fuel was all that was needed to get the knock under control more. I'm still experimenting some with different WOT fuel targets to see what it seems to like best.

Rev6.hpl
stockWithoutTorqueManagementRev6.hpt

[Hemituna]

These things need very little timing to make power.
Yes, Dodge have em fairly aggressive stock.
Runnin em cooler helps as does fine tuning cam timing and spark
The stock knock sensor settings are usually good till you make it real noisy or add a blower and its mech noise
But if it is false knock, you will have near on zero timing in it and it will still be retarding.

[tbrtuning]

Thanks for your response. Without changing the thermostat I'm guessing I can't do much with the fans to make it run cooler? I haven't found a table for WOT cam settings. Am I missing something?

Did I get torque management turned off where needed or do I need to do something with the engine torque management or engine diagnostics tables? I guess I should try logging more parameters to see if it indicates that torque management is active.

[tbrtuning]

I logged just driving around today and got 3 counts of knock just casually braking at one point and the road was smooth. Was getting 1.5 just driving along hitting rough spots in the road.

Any common place where things end up making contact causing noise on these cars?

I also noticed my fuel trims were all over the place. Makes me wonder what it is doing at WOT. When I have more time I'll replace an O2 sensor with my wideband and check, then turn off the NN and tune VE. I was going to do it today but the front sensors is a pain to get to. Would there be much difference in reading at the front sensor vs the rear one in the cat? I usually just put my sensor in front of the cat if the car has them.

[FlyinRyan]

My rule of thumb for knock sensor settings on the Hemi cars is typically to start by dividing the timing to pull after first/continued knock settings in half, and cutting the decay rate in half as well. Then, I will desensitize the sensors as needed. With good fuel , a catch can, and keeping them cool, They still don't want much for timing but there is room for improvement. I am picking up 7-10 whp peak on your typical 392 car, and I've seen some cars pick up 30-35 whp in the midrange with bolt-ons. DO NOT RUN THEM LEAN, I'm finding consistently they seem to like 12.0-12.2, and leaner than 12.5 really pisses them off.

[TurboCamaro]

Ryan
With supercharged 392 Challengers how far have you had to desensitize the knock sensors.
Thanks

[2therock]

For whats its worth on my stock 2013 5.7 Hemi (180?F T-Stat / K&N Drop-In / Corsa Sport) they only netted 10+ HP and TQ on the dyno. So I guess Dodge put most of it on the table with the 5.7's eh?
He did have to adjust the K-sensors just a little. On a hot 98?F high-ish humidity day with the engine at full operating temp a WOT run pulled 1.5? in only two cells. I only run major brand 93 octane fuels.

But, this and other calibrations he did elsewhere in the engine and trans made the car run and feel like it got 25HP. Most of it shows up in auto-stick.