hi, i trully appreciate your input, its made my life a lot easier. so now i have to come up with a tuning strategy

when tuning these FI S5s did you use any external systems (like det3, standalone, etc), or everything was mapped into stock ecu using KFMIRL/KFPED/KFMIOP & any others? -- or even patched a boost pid??

Supercharger is a lot easier to tune for decent part throttle response vs turbo/twin turbo. And because it's mechanical, there is no need for any kind of boost PID, LOL!
I've tuned those cars 10000% on stock ECU without anything external only by using KFMIRL/KFMIOP/KFPED/KLRLNMXN.

KLRLNMXN is the LDRXN, but why do you care? With a supercharger nothing much changes.
The only issue is that pressure ratio will have to be baked into throttle maps, but it can be done because there is a mechanical 1:1 relationship.

With turbo there isn't, and it's a pain in the ass to make it drivable.
I certainly did algorithm modifications on all N/A ME7 that I tuned with a turbo on them. Specifically the throttle WOT algorithm needed mods as otherwise the car drove like shit with constant throttle cuts and not going WOT when it should.
And then the ECU needed turbo control based on ps_w: https://github.com/prj/C167BoostControl

You have 5 pages of text in here about theorycrafting. You're not going to be able to tune your car by theorycrafting here.
I can count the people in this forum on my fingers who actually went through the trouble to boost a N/A ME7+ car with turbos and actually succeeded in making it drive properly.
Most of the cars you see online drive like absolute shit on part throttle. With frequent jerks, throttle cuts and other issues.

And I do hope your car at least has a manual transmission, because if it's 6HP then that's yet another topic, which almost nobody in the aftermarket understands properly.
And no it's not going to run well without extensive adjustments.

It probably won't happen even in 5 or 6 years to get it running right.
Especially on 6HP.
Unless you take a shortcut and manage to find someone who will do things for you.

The thing you don't seem to understand is, that anyone can put together an older mechanical car.
Even on this car the fabrication is nothing special, at least there is no shortage of people in the world who will be able to fabricate all this.

But to do the software right is very difficult, and there are very few who could possibly do it, to a level where it runs well.
And the vast majority of those people are not going to give you the time of day.

Btw, theorycraft on a forum is not a "project".

Anyway, I'm done here.

I gotta agree, its time to put the "theories" to the test.

Even if there is no rlsol cap , go ahead and request more than 100% load, which will be one thing, but can you get your actual load over 100% too?

You can do these things right now with minimal effort, and you can go on from there.
The automatic trans is going to give you major headaches for sure, SPECIALLY depending on how you will achieve boost control and load/torque shenanigans vs a turbo project.

And yet, theorycraft is exactly what you're doing here. on the S5 specifically, rl_w does and will go above 100% without a problem

less talking - more doing.

Nothings gonna get done by talking about it. NO ONE is gonna give you the answer or do it for you.

Something tells me you are gonna talk about this until the cows come home and make zero progress other than dreaming.