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Drunkmann Tuning's Recommendations & Guidelines 

Cobb AP Data/Gauge


A/F Correction #1

Make sure the Min/Max at idle is never +/- 25% sustained ( and not moving from).  

Simply A/F Corr #1 is the amount in percentage of the instant fuel trimming needed to target an AFR, usually stoichmetric, (14.5-14.7) in closed loop. This is based the MAF Voltage and the static MAF Scale/Estimated Air Mass (measure in grams/sec) inputted for that specific MAF voltage. 

Further explained, say at 1.42 volts on the MAF scaling says it should be at roughly 5.15 grams per second of air mass, the car knows to add the specified amount of fuel needed for 5.15 grams of air mass.

However, various imperfect factors are always present. So basically, front o2 will read the AFR as a bit leaner than what the AFR target is and the car needs a more fuel.

Well the A/F Correction #1 goes to work. It will make instantaneous changes of global fuel adjustment to add/subtract to hit that requested AFR target and using the front o2 sensor reading to judge correction amount instantaneously. 

This is the function of simple closed loop fueling theory. However, the stock narrowband on MAF driven cars are there mainly to trim fuel in the cruising/idle air/fuel ratio in lighter/closed loop loads.    

 Driving around it will kick around a good bit especially sudden accel and decels. Usually, once you're in medium loads, few pounds of boost or past 65% throttle the this function will disable as you will be switched into Open-Loop Fueling which uses the MAF. In open loop it disables the short corrections and ALL fuel is calculated by the MAF voltage and Air Mass for that voltage range (or simply termed  MAF scaling). 

Again only under idle or very steady cruising the A/F  #1 (Short Term Fuel Trims or STFTs) will be stable. This data will tell you if you have a vacuum leak etc. If there is a leak it will sit at full +25% correction and likely will sit leaner than 14.5-14.7 it's adding fuel to try to target as well.


A/F Ratio #1

This is the stock NARROWBAND  sensor. Should be around 14-15s soft cruise/idle and low and 11s  wide open throttle on the monitoring device. Anything below 13.0 AFR (12.5-12.9 is even iffy) is getting pretty inaccurate. Anything richer than 12.0AFR the stock NB AFR Sensor is COMPLETELY UNRELIABLE!!

Hence why you should by a wideband and as the name suggest has a wider range of available reliable range of AFRs. Usually wideband sensors can read as lean as 17.9-19.0 AFR and as rich as 9.0-10.0 AFRs depending on brand. For this reason they are ALWAYS recommended with these type of narrowband closed-loop type application. Never trust a narrowband for WOT fueling.


(Manifold Relative/Gauge Pressure is simply absolute pressure with the current atmospheric pressure subtracted out. This is mainly to make positive pressure (boost) easier to identify, so anything over 0psi relative is positive boost pressure.  Easy.       

This max or peak should ideally be within +/- 1.5psi of the peak listed on the map or notes/descriptions of your ProTune. 

 (Maybe a momentary + 2psi overshoot momentarily in higher gears is possible;  however, should correct within a few milliseconds using the PID theory  in the ECU and TD correction). 

NOTE:   On the monitor screen "Boost" it may error out in certain throttle close or other  situations where it will max the voltage range out on your MAP sensor (manifold absolute pressure sensor) almost instantaneously it will disappear. It is usually always a voltage spike on throttle close on Drive-By-Wire cars. However, the 16-bits and/or Drive-By-Cable will also throw the MAX voltage (24.14psi) as random  errors quite frequently even full boost or mid-pull and will show it super fast. It is just enough to see it in a random line or two in the datalog. It usually only a errors for a couple lines in the datalog out of 30 or more lines showing accurate boost levels otherwise. 

(Just ignore the 24.14psi in the min/max under the boost monitor when it's an obvious error).


Feedback Knock Control

Ideally should  be -2.11 or less Wide Open Throttle (WOT)  however may kick up to -8 to even -11.98 (rare) just driving around normal from driveline noise/chatter to "burst knock." Usually it's a crazy fast burst and decay and usually always simply noise/false knock agitating the knock sensor. This doesn't necessarily mean actually det, knock, or pre-ignition. In most all cases if a false reading from the KC.

 Also sudden/hard throttle changes/opening can also kick a some FBKC which shouldn't be worried about. if the car is off-throttle and smash pedal fast at a lower RPM usually can kick FBKC but should start decaying out almost immediately. If you have severe knock control issues, like seeing no FBKC and your DAM is unstable start by cleaning the metal base of your Knock Sensor then re-torque it to exactly 17.5 ft/pds. Usually on rebuilt motors the tech will over-tighten or leave it too loose. It is imperative to be torques correctly for proper functionality and noise filtering. 

E.g. seeing higher FBKC Min/Max Values:  You were driving around town and happen to look down at your monitor and see a random -6.33. It is very likely you just it's just false noise the  knock sensor and or driveline noise. FBKC is subjective as these cars as they use "blanket" knock control theory with mediocre noise/knock filtering.  

So at WOT in gear steady pull and a SUSTAINED (not lowering/decaying out) of -4.22 or more would likely a true knock correction and if it happens more than randomly needs to be sorted.


Fine Learning Knock Control

This will vary and as long as you don't see any more than -4.22 being pulled should not be of concern. This is constantly adapting. So if you see a larger number could be a variety of things, give it a few more miles to keep learning and usually always decays back out within 50-100 miles if you are able to hit the problematic the load range without further instances of knock correction being triggered. Bigger than -4.22 FLKC, along with more than normal FBKC it is likely a smaller gas quality change or leak/fueling issue and needs to be checked.


Intake Air Temperature

(also for Boost Air Temp used in Speed Density IAT relocation)


As a rule of thumb, make sure you NEVER go crazy beating on the car [WOT] +40 degrees over ambient temperature. The car is heat-soaked and needs to cool off. Why? At this point the timing compensation tables are pulling up to -6 degrees from the entire timing range, and will lead to incorrect tuning due to the car's compensation.


I general do not recommend to floor the car over 135 degrees (F) for Speed Density; and 145 degrees for MAF. Simply drive the car normally and somewhat conservatively until the Intake temps come down as fresh air is introduced. If you have consistently high IATs above 125 degrees you're throwing power away as heat temperature compensation will automatically pull timing out above 125 for MAF and 115 for SD.


Full Speed Density relocated IAT

(considered a boost air temp sensor now or "BAT") owners only; potential traffic "heatsoak" issue.

When/if you sit in traffic for extended amounts of time on a hot day and the car is sufficiently heat-soaked drive the car very easy until your BATs cool down some!! 

Basically SD is based off Temps (The Ideal Gas Law say density of air changes at a fixed rate per temperature gradient change and static), Manifold Pressure, and Theoretical Air Densities/Efficiency is calculated outputting a calculated fuel almost instantaneously. However, when you heatsoak the car with a "fraudulent" heat-soaked temperature the ideal gas law is no longer accurate in trimming total fuel output based on temperature. Make sure you BABY the car until BATs are back down to much more normal levels. If at ANY time (usually above 160s BAT) the starts to feel hesitant, super sluggish, and generally "off" pull over pop the hood in the shade for 15-20 minutes and let the BAT/IAT piping area cool, then resume normal driving conditions.


The extra hot piping, limited airflow underhood condition and surrounding area's radiant heat will falsify the true incoming air temp to the manifold via radiant heat transfer through the sensor itself. Your fueling is based on theories, so if there is an external factor or condition soaking/falsifying the sensor data this Gas-Law is no longer accurate and neither is your fueling. 


This is also why you NEVER want to put an IAT sensor bunged directly into the intake manifold.  I have found GMs to be very unreliable as well, so just buy the AEM and not have to constantly replace them.




(Most Important!!) = (For Mainly Pre-DIT Vehicles)

This is the one that will tell you if you're car is severely knocking or not.


A DAM numeral of 1.0 is considered  a full Dynamic Advance Multiplier.  


Which generally means safe, knock free and the 100% of the (KCA) timing map is added onto your base timing map increasing your total timing to the range we set it to when we tuned it. A full DAM is what you want and almost always should be on 1.0 in most all driving conditions. 


However, if it drops by .25 DAM value (or 25%) it is one course (severe) knock correction. So now you use 75% of the additional timing map lowering the effective total timing to increase the resistance to another detonation event. However, severe misfires can and will also cause a DAM drop, but it's usually always to .8750. This minor DAM dip is usually always a misfire. So a DAM of .8750 means you likely just misfired and don't panic; however,  a  .75, .6750, .5, .4750, .25 etc or less that likely a pretty severe knock that is likely ongoing and need to be service or looked at immediately! Again, DAM philosophy is .25 of DAM representation is equal to 25% global reduction in the knock advance timing map. So if the DAM drops by .25 it's usually always a coarse knock correction event (big det event) and you need to contact me.  


With the DAM at .5 (after two course knock events) you are running ~2-3 degrees less timing than normal. It is important to note if your DAM takes a hard hit and below .75 you need to contact me for ways to test and recover from this safely to prevent damage to the internals of the engine.

Eg. So if your DAM is at .50 you had two big detonations. Post tune big knock events are almost always cause by post-MAF leaks, failing MAF, and simply/most often plain crappy gas. 


16-bit DAM Logic : A DAM of 16 (meaning 100%) are representative of the overall percentages of KCA timing map being used. 

Note:  DAM Philosophy for 16-bit (02-05 WRX, V7-8 JDM STi) is used by multiples of 4.

So a 4 point DAM change is basically (25% of KCA map) x 4 = 16 (or full 16 point DAM).  Basically the same as a .25 DAM drop on a 32bit ECU. They changed the numerals around to make it easier to monitor. 

DAM of 16 means it's running the full values in the knock advance added in and relatable to the 1.0 100% DAM on the newer ECUs. The only difference is in the 32-bit a full whole number (1.0) represents  100%  and the 16-bit is simply in multiples of 4. 


However, most times a misfire on a 16-bit usually drops by 2 DAM points. A course knock correction (bigger knock event) will usually always kick it by 4 DAM points, so a 13-15 DAM is likely miss-fires and not severely knock. 


Again, severe misfires on the 16-bit ECU will drop the DAM by 2s and eventually working the DAM down as low or lower than a course knock correction.  So it's important to find where it drops the DAM and under what condition. That is the reason why this should always be monitored whenever feasible.  If your CEL is flashing this is severe MISFIRES and usually not knock related unless you have a CEL knock flash enabled (Like a Carberry ROM or something). 



Good luck and happy monitoring!


Anthony J Berry

Drunkmann Tuning-EFI Calibrator and ProTuner

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