Knock detection/monitiring, MAXXECU SPECIFIC KNOCK CONTROL. Fueling/closed loop control

Hello

I run a Maxxecu race Ecu on my Evo 8 and i have it running well and making decent power/torque, it's fairly conservative on ignition timing, any 4G63 fanatic will know that these engines are down to single figure ignition advance numbers in the high load areas and in my opinion the 'safety window' is narrower.

I'm in the UK so i can only run Pump Fuel (Shell V Power 99 oct) which again makes the 'window' smaller.

Up until now im using Phormula KS Pro Knock detection although i have to admit i prefer the DIY style Ear defenders and tubing to the engine block, I feel safe or 'safer' with these, obviously theres no way of filtering out unwanted noises etc but if i was to do my final pull to verify things i would choose the DIY method first!

Of course a load bearing Dyno is the obvious answer and yes i totally agree however we dont all have readily available dynos to hand, i've been road tuning for around 10 ish (i am just a hobbyist kind of tuner With a good understanding of how engines work & how fuelling and timing can change things) years and have acheived good results and so far i haven't severely damaged an engine, once my tunes have got to the stage of dialling in timing i like to read the plugs as in my opinion this is a true and accurate way of checking for knock/pre ignition & mixtures, i'm a 'half way down the plug strap' kind of person lol

As many will know, Maxxecu Race has onboard knock control which according to my research it does a good job when setup correctly which brings me to my main query..

I find Maxxecu's instruction/help menus could be a little better, professional tuners getting there feet wet with Maxxecu for the first time will no doubt argue with me but i'm far from a Pro!

My understanding is that you obviously configure the Knock system with your bore size etc, then in this order you would do the following:

1) Do a WOT pull when you are sure theres no knock, with a very mild advance table

2) Induce some knock in the light load areas

3) Do another WOT pull whilst logging at the correct Hz and monitor the appropriate channels

4) Populate the sensitivity table ideally with values right before actual knock occurs

4a) We must 'teach' the Ecu what actual knock sounds like in order for the system to even begin to work correctly

5) Setup the ignition Retard table to pull timing out when knock is detected

6) Populate the 'Recovery' ignition table and also the recovery speed in degrees per second

7) Hopefully then allow the Ecu to save my engine in the case of bad fuel etc etc

As i mentioned this how i understand the Knock strategy to work, obviously there's more to it than this but i think i've grasped the bare bones essentials. I would like to here peoples opinions, even criticism would be appreciated! We all must start somewhere. I feel i should mention that my engine still retains the factory balance shafts and i don't run any uprated engine mountings which are known to create unwanted false knock events to further complicate things!!

FUELLING:

At the start of my tuning journey i would usually disable any closed loop corrections and 'manually' dial in the fuel, many many datalogs and looking at things like;

1) Lambda target & Error

2) Look for the Peak torque areas of the engine where airflow begins to fall away, the highest VE values show when we have found the Peak

3) THEN once i'm reasonably happy with the tune, Enable the Closed loop lambda control, I always set this up with minimal authority, reason being is I believe that drastic fast lambda corrections can cause huge swings and lead you to correct manually

4) I initially aim for 10% maximum error and then try to fine tune to within 5% of my targets. Also as a rule of thumb i NEVER allow the system to pull alot of fuel out in the high load areas, in my opinion this is where you really start to see how good a job you've done! Also at every opportunity fit a new set of plugs and read them after a pull.

5) Once i consider the tune to be say 90% there, i enable the Long Term trims and over a period of time look to see any repetitions of +/- trimming, i would aim to cover a good 500 miles over as many conditions as possible, weather changes, warm/cold days, all Revs and load.

In my opinion its all too easy to allow the closed loop system mask a bad tune especially with how good CL systems are these days, i feel better doing as much as possible MANUALLY - so no corrections, i think i see Closed Loop lambda correction as a tool to to see varying trends in the fuelling. NOT a click click, enable, forget!

Again i would love to hear opinions, criticism, views etc, like i say i have been Tuning for around 10 years so certainly not an absolute beginner but like every thing else in life, every day is a school day and there's always time to review what you think you know and accept criticism as a Positive!

I'm interested in ways to do a better job, I would love to be able to enable the Knock Control system and be more confident of having an extra 'Pair of eyes & ears'

Hopefully my methods and understandings are fairly accurate, i always think that if the engine is still healthy, plugs look ok so it must be ok lol.