Closed loop-only operation

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I'd like to start out by saying that I'm a software engineer with almost 20 years experience. So I may be a bit biased when I look at a piece of software like Hondata Smanager and think about the improvements that could be made.

Basically what got me on here posting is that I'd like to be able to run closed loop all the time (i.e. have the ecu able to adjust the air fuel ratio while WOT), but I can't seem to get the rate of change to work that great (or maybe how I envision it working/as well as I'd like it to work).

I came up with the concept of setting it up to only be able to add fuel but not remove any above a certain RPM, since I don't want it to accidentally go lean at WOT due to the closed loop swinging the afr with the rate of change (I can get it pretty close by lowering the numbers down and it will stay within 14.4-14.9 cruising for example but then it also adjusts really slowly).

I know I can accomplish (kind of) the same thing by setting the minimum short term adjustment to 0 (so it can't remove any fuel), but that will also mean it can't remove fuel when I'm *not* WOT so I will basically just lose out on fuel efficiency when cruising around. Either that or I would essentially have to tune the maps either just slightly rich or spot on so that way it only ever *needs* to add fuel, but even then I would probably end up erring on the side of rich and probably be cruising at like 14.5 which isn't the end of the world BUT I think it would be easy enough to add RPM based closed loop min/max adjustment. It would stop me from having to perfectly tune the entire table (which is going to take a long time due to not having a dyno and being able to hold constant rpm to target each cell and get it dialed in). I think eventually I could maybe get there but it will probably take me months to years to really get the whole thing perfect to where I could set it to never remove any fuel.

I'm thinking it would basically be easier to just have two RPM based tables (similar to the rate of change tables/max TPS tables):

Minimum short term adjustment:
Under 1000, 1000-2500, 2500-4000, over 4000 rpm
-15, -15, -15, 0

Maximum short term adjustment
Under 1000, 1000-2500, 2500-4000, over 4000 rpm
47,47,47,47

That way you can set the min/max based on the engine speed, so that under 4k rpm it can both subtract and add (based on the min/max you want) and then over 4k I can set the min to 0 so it can't remove any fuel (only add if it goes lean). Obviously this is just an example, I would really like it if it was just a 4 or 5 cell table and I could edit the RPM range values on the top row and the minimum/maximum trim values on the bottom row, similar to the 'Max TPS' tables and then just have it interpolate between them and set it to what I want.

This combined with the rate of change table would allow me to feel more comfortable using closed loop at higher rpm knowing it isn't going to remove fuel on me and cause it to go lean while also still having it set up to be able to correct quickly.

I think the obvious choice is to just "go to open loop and tune it to the correct afr" but I don't really want to always have to monitor/adjust the tune, I should be able to get it close/spot on and then set closed loop and forget about it and not have to worry about running lean randomly or constantly adjusting the tune based on a bunch of external factors (humidity, elevation, crappy pump gas, fuel tank pressure, etc.). I just feel like it could work a lot better than it currently does with this change.

Anyway this was kind of a long post, the only other thing I wanted to ask about was it seems the maximum closed loop RPM is stuck at 8k, does a value of 8k for the 'Maximum engine speed' value disable open loop? Or will it go into open loop above 8k, since I can't set it higher (or is there another setting I'm missing that will allow me to raise the max engine speed value?).

Thanks for taking the time to read this whole thing and I appreciate you guys over at Hondata, I just wish it was open source so I could just make the changes myself (honestly like I mentioned I'm a software engineer and if you sent me the code I would be willing to implement it and give the update to you guys for free ... not that I expect you to do that but just throwing it out there). It's possible other people would also get use out of this feature, I've seen a couple different threads online talking about running closed loop 100% of the time.

Anyway let me know your thoughts if this is something that could happen, also let me know about the 8k engine speed thing, not sure if I can raise that somehow since I'm spinning to 8.2k or if I should just lower my rev limiter to 8k so I don't go out of closed loop.

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Sorry for the double comment, it wouldn't let me edit the original but I had a follow up question.

Would setting the 'fast - lean to rich' (or fast - rich to lean, can't remember which) setting to 0 above 4k stop it from removing fuel? I wouldn't think so since I would still have to have the 'slow' setting above 0 ... just a thought, let me know.