Dodge fueling options and knock sensors

[Phil'sC5Vette]

two part question on fueling and knock sensors. Read both and in-depth answers to both please.

Injector pulse width Vs Fuel Mass = INJPW vs FM
Fuel Mass Vs. Injector pulse width==FM vs INJPW

Im very comfortable with the GM line vehicles, but like most of us, im getting up to speed on the Dodges.

1st question: while changing the FM vs INJPW, which end of the scale is idle and which is WOT. Which is WOT the 0.00 end of the scale or the 1.02 which in my GM head is G/Cyl for WOT. As im writing this im thinking the 1.02 end is WOT.

Can anyone confirm which end is idle and which end is WOT ?

2nd question:

Either the dodges cant handle much timing, or there knock sensors are very sensitive and always knocking.

If you were to desensitize the sensors, can someone write a quick step by step on how to slightly desensitize them and which ones? Looking for a good step by step. Pictures help me learn. Please no one line explanations.

[Jay@HAP]

1.02 is the upper end, WOT fueling

Dodges don't like much timing and typically the knock sensors are very sensitive.

[Homer]

Answer to Q1:
fuelmass.JPG

Partial answer to Q2:
I think you first want to determine if the knock is real or other noise from the drivetrain. You could log a run at your intended octane rating for the tune and then repeat the log while running octane boost/racing fuel. Then you look to see if you are getting knock at a consistent RPM which is most likely an indication it is some other mechanical noise source the sensors are picking up and not knock. As for actually tweaking the sensor setting, I have only used the setting from the Diablo 93 canned tune which is very similar to the settings magnuson uses in their base SC tune (I will post stock and 93 tune when I get home later today). Be careful messing with the knock sensor values, there was a gentleman on the CT forum that desensitized them too much and wrecked his motor.

[Jay@HAP]

log knock sensor voltage. that will give you an idea of if its really knocking or not. Depending on the year, the knock sensors are on a 0-5v scale. If you look at the thresholds, some are 1 volt which isn't much.

[Phil'sC5Vette]

Well articulated responses. Thank you for the clarification. I've compared a couple of the stock tunes I have with a couple of the Diablo tunes I have on the same vehicle. Most of the time they change the knock threshold only on cylinder 1, and sometimes increase that 1V higher on each cylinder.

So Jay, to clarify a higher voltage would desensitize the knock sensor and lowering the voltage would increase how much it hears.

We know we should be carful with the sensors, but I wanted to understand what a higher or lower volts does.

[Jay@HAP]

Correct. Raising the voltage desensitizes the knock sensors.

[Homer]

BTW here is a stock and 93 tune to help give you an idea of how much a canned tune desensitizes the knock sensors.

93.hpt
Stock.hpt

[Phil'sC5Vette]

thanks got it