i am posting this to try and help everyone understand why they are getting random real kr in their lnf's.
this is most likely going to be a long first post read so have some beers ready to help you make it through.
The LNF is an amazing motor and i enjoy building them as much as i like to ram them full of absurd amounts of boost and hope they hold together but as we know the biggest downfall to this engine combination is the ECU.
First lets explore how most of the operations are tracked and controlled by the Bosch E69.
Torque Modeling is the name of this game and to do so we monitor a variety of inputs to help perform a calculation which allows us to see the load in a percentage. This output result is called calculated load and it is derived from sensor input data rather than a properly calibrated testing rig of the engine flywheel or vehicle chassis style.
Calculated Load drives the x axis on darn near 90% of the tables we see in the E69 to date. The axis at its longest form is only 14 cells long and at its highest value only reaches 210% load. When you raise the boost what happens? come on booster were not stupid the load goes up! Fantastic! people here listen very well from what was started in 08, makes helping everyone that much better. Anyways, back on track you will all notice that around 18 psi or sooner in some bolted on cars the calculated load exceeds 210% load.... wait if it exceeded the axis labels what happened? OH your catching on now! The axis labels in some E69 Series are editable which is good for you guys with pure race motors because you can adjust those axis labels to help you make adjustments in the higher load ranges where your more worried about controlling the engine for sustained/long abuse. Booster...Why did you not say its good for us daily guys too? Well its an easy answer, in one word form its "Clarity". The more axis plots you have the more clear a larger selection of incoming data will be simply because you can monitor more points along the way. This is why Motec/Haltech/Big Stuff/Mega Squirt are all pushing to or have passed the 16 x 16 axis plot limit. The more power you make chances are the larger your sensor ranges will become..if you only get 5 plots and you have to read from 0-200% then you can only adjust for 40% load shifts while the computer is left to calculate everything in-between. now going to the LNF E69 we get 14 cells with a maximum of the factory limit 210% that leaves you with an even spread of ~15%. now most people here pushing the engine to its limits have been able to touch 300% load ranges, and that puts you guys with a spread of 21%. because you are now leaving the computer to figure out the in-between for a larger gap your clarity has dropped.
With clarity explained this is where you guys run into the real random kr issue and that is you don't re-adjust your axis to allow for covering the new maximum range of your setup. everyone tunes to the factory axis plots and thats great but when you go massive turbo and hit 350% load you are leaving the computer to calculate and adjust on its owns for a 140% range of load. Where is its base values to help get it on point? How off are the trims from run to run as you troll through that un-plotted range?
But Booster i dyno tuned my car and its was perfect and now its not happy on the road, or vice verse, i tuned on the street and now its in limp mode on the dyno whats happening?
I will tell you all once here, right now... You have exceeded the max limit of your ecu factory axis capabilities and left the ecu to calculate the off the map stuff by using the last known plot that exists on the chart. in doing this you can achieve very similar loads on same day street runs and especially on a dyno that is designed to allow a rate of acceleration. Now that you have tuned the last cells on the table to match these conditions you take your vehicle back to the street or put in on the dyno after butt dyno'ing and end up running through a different load than you previously encountered. now the last cell plotted have to be changed again to meet the new environmental changes causing different load results.
The answer:
Changing your axis values to cover that uncharted range will allow you to tune for both conditions. im not saying make your tune like mine but this is what i do for race setups. in order to cover more load varying conditions in the high load range i leave fewer low load cells on the table usually 20% and 50% then i immediately start at 100% then evenly space them out till i hit the max capable load for the setup. ( you will not know this cap based off of added on parts. it will take you run after run raising the power limits and seeing how high the calculated load goes to find the proper max load value) for example though we will say max load is 300%. i just used 3 columns to get me to 100 so now i only have 11 left to plot in so (300-100)/11= ~18 so plot it all out. 20,50,100,118,136,154,172,190,208,226,244,262,280, 300 now yeah i know it wasnt perfect so the gap between the last two plot points was a little more than the rest but it is only 2% which is small compared to not having any coverage there. now as i tune it i will fall into ranges that allow me to cover everything i need to helping to eliminate false and real random kr. Varying load without coverage is the number 1 lead to LNF engine failure under high load conditions.
The only way to get enough clarity to include daily driving in a high power setup would be to expand the max allowable amount of plots on the axis. Since the only way to do this is to run an M1 ECU for around 6,000$ before installation and tuning the majority of us are left to the current options that we have available and as of now its re-labeling your plots.
This is going to be a massive overhaul compared to the well i just want to raise the power some tunes that have been getting performed but due to lack of people consistently verifying the running operation of their vehicles i was left no choice but to put this out in an attempt to help prevent a few more motors from becoming recycled material.
I will answer as many questions that i can but this should at least get the questions back out to the public for review rather than staying locked in our heads.
Alex
CSSOB
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HATE this fkn weather!