What table is the Copperhead PCM looking at when spark source is 'base'?
What table is the Copperhead PCM looking at when spark source is 'base'?
I could be wrong but I believe whenever I've seen base as the spark source, it looked like it was related to the MBT table clipping borderline.Originally Posted by txcharlie
How does MBT clip borderline unless borderline is edited to be higher than MBT, which would be a tuning mistake, no?
Not necessarily.
Borderline as Ford does it really does represent "this timing is the borderline to knock". In some cases (low load areas mostly), you can run more timing than MBT before knocking. As such, the borderline table in these areas is usually mapped out higher than MBT.
"Base" spark source is basically only at low load from what I've seen. If your strategy has Spark Limit Source, log that to see, and it should show MBT.
Mine isn't like that at all. MBT tables are all quite a bit higher than Borderline and the spark advances off borderline values up to MBT table and I assume also retards if needed off borderline but at part throttle I have really only seen small advancements and no knock but my car is stock.
Maybe the logic is different for 2015/2016, I know the Spark Ratio stuff is opposite as well based on what I have seen on this board.
I get exactly what I command at WOT in the Borderline Tables, not the MBT tables, and I have not seen my Spark Source show MBT at all.
Saying that, I realize this is a Copperhead thread. I think my 2016 ECM is Fluffy Pancake.
I have looked at the area I am getting the 'base' reading and BLT is not higher than MBT.
The reason it is an issue, is I'm getting a small amount of knock and it shows 'base' for spark source, so changing my BLT does not resolve the knock. It's happening at low RPM/Load.
I am using the Roush spark tables, which are considered very conservative, with E85 and still getting this knock. I have almost concluded that it is false knock, as the tune from Roush comes with the KR sensors turned off.
Last edited by txcharlie; 11-19-2015 at 01:19 PM.
How are people getting consistent timing with these things? IAT, ECT, Lambda Spark, and Knock Sensors aren't that bad to account for, then you have global adders for each cylinder(for some mapped points, but not others, this means you can't just set the higher load/rpm of all the other mapped points to be the same as OP), transient(how is 6500rpm, 1.00 load transient?), octane adjustment(thought the knock sensor already had this covered), it's pretty crazy. I couldn't imagine keeping a power adder car at a consistent safe spark value.
Last edited by AKDMB; 11-19-2015 at 03:23 PM.
Consistent spark is easy. Mines the same every wot pull, and down low at part throttle input/low loads. Never changes.
Just tuning the borderline OP table mostly? Eric is working on adding the knock sensor PID for my application, so I haven't been doing any spark tuning yet, I've just been looking through my tune trying to get an idea of what I wanna try to do. I might make a separate thread about some of the settings, like the global adder/ mult, transient, and some other stuff.
if you are picking up knock with roush or any stock-like spark values on E85 it is definitely false knock. you will be way past MBT (actual) before E85 knocks.
how do your plugs look?
+1
They look good to me. What do you guys think? (This forum does not like any of my attachments!!)
https://onedrive.live.com/redir?resi...hint=folder%2c
Last edited by txcharlie; 11-20-2015 at 07:57 PM.
I would use a heat range colder spark plug. What is your WOT spark timing? Does the ECT affect the spark retard?
Russ Kemp
WOT is only 10*. I'm not having any issues with knock at WOT; only low RPM/Load. ECT only pulls spark at 250*.
You think a colder plug is needed with E85?
Easy peasy..My Twin turbo Coyote 13lbs on E85 commanding 20* .760 commanded Lambda is dead on
Personally,I do not allow the Knock advance to add..
Last edited by 98BlackMomba; 11-22-2015 at 08:30 PM.
Did anyone ever find the answer to the OP's question? What table(s) are being used for spark advance when the Spark Source is Base?
I always thought base was MBT like stated originally. Looking at the table and seeing that MBT is higher than Borderline so it isn't that is invalid because there are many modifiers to spark.
MBT for Fords has generally been high, like 30* or more at high load / high RPM, same goes for my EcoBoost 3.5 - but the problem is at WOT (like at a drag strip), my final spark advance is only 9*-11* but Spark Source is "Base".
I can read PIDs for Borderline Knock, MBT Advance, Spark Advance, and Spark Advance (SAE).
For example, The Borderline Knock (16*-17*) and MBT Advance (35*) correspond to the actual tables, but Spark Advance is much lower (9*-11*).
Bumping this up as I have the exact same question, in my tune and logs, I go over to "Base" spark source right around 6400rpms at WOT, and am having trouble getting it higher as my borderline spark is higher than what is showing as final timing and MBT is higher still.
This is what I did for my SHO and from my write-up and YMMV:
What happened was my SHO would use "Base" as the spark source even at WOT. I couldn't raise/lower the timing by adjusting MBT or BKT. I experimented with the above settings and now I can just add timing to the BKT tables and have an impact on final spark. For the SHO, I only have 6 mapped points. Keep in mind the SHO's 3.5L EcoBoost only has Intake VCT. The F-150 3.5L EcoBoost is Ti-VCT, and I believe Coyote and other Fords use a LOT more mapped points than 6.I found that table 32396 Spark Retard for Combustion Effects (Combustion Effects) should be all 0’s (I found this from the stock F-150 EB tune). For table 50227 Spark Low Load Max (Low Load Maximum), the entire column should be “55”. The tables for Cyl #1 Mult and Cyl #6 Mult were all made 0. Under table 38053 Spark Cyl to Cyl (Cylinder to Cylinder Offset), I changed the “-2” values all to “-1”. The PreIgnition Limit and Cylinder Pressure Limit tables were all set to 63.5
On the GM LNF, a few tuners tried to explain to me how the spark tables worked - it is similar to Ford's MBT and BKT. But for the LNF and the Fords, I just add the amount of spark I want to the high RPM / high load region (basically 3500+ RPM and 1.00+ load for EcoBoost) for every mapped point table. Others have used the weighted values to determine how much to adjust for each mapped point, but that's too much work for me and especially since the SHO only uses like 1 or 2 mapped point tables at WOT. I never felt the need to mess with the low load / lower RPM spark cells with the EcoBoost or the LNF.
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