Your approach on tuning with Meth Injection

[Nastruck]

So I'm curious how other peoples approach is to tuning with Meth Injection. Cause when you start spraying meth the AFR goes rich and your AFR error is thrown off and can't really line out your fuel trim cause its now richer from the added meth.

Do some tune it without meth and turn meth on after the AFR is lined out. Or a different approach. I could see this way working on low boost with meth added for more safety. But on high boost apps doesn't really sound like a good idea to tune without it and add meth afterwards. Looking for some insight on future tunes since all the local guys I've been tuning are now starting to get into boosted setups.

[Area47]

on my own car in the past, i baked it into the maf scaling to get the commanded. then kept an eye on the afr.

[MMGT1]

Calibrate commanded Lambda first. You have to know your fuel is there before adding Meth. Once you know fuel is correct, wideband to .75 to 1AFR below your fueling target. If your in the 14psi range I bring Meth in at 6psi and full in by 10. I run the Meth a little deep. Bone stock 3.7L Ford that runs 10's and head temps are lower at the quarter than the launch...lol It actually drops temp shifting at 7k rpm.
Edit: Your meth kit will come with different size jets. From those you choose the one closest matching to the HP the vehicle makes. This way your not just pissing in the wind as to which one to install. To be super safe, Ill install the biggest one they have, no matter what, and work back from there. Same principal that I set timing stupid low when working with boost to start. You have all day, dont rush when playing with Meth. Low and slow...

[Nastruck]

What about people running. Built motors over 14psi. 20+ psi which I wouldn't think lining on just pump gas is all that safe without meth

[MMGT1]

This is what I did, I may be in left field, but it has worked for me. There are trends to a curve that you can be pretty darn close with fuel. I don't just rely on plotted points when you make that kind of power. Come in slow. Look at the trend that the engine is taking(MAF or VE, whatever your into). Use that to "predict" what the motor will want and add a little to that. Then bring the engine into that range, check that you are indeed following the trend you see happening. Couple of pulls and you'll have it dead on. Meth is cooling those charges and actually takes up space that would normally be occupied by fuel. Low timing and set fuel. Once Meth is added, then you can add timing and make the power your after. I had this one at 17psi but it was just too much for the stock internals. Meth is making our 93 pump gas run 118 so I'm able to push 20*. Without meth 16 is close to disaster. I started on 10* to begin with. What I'm getting at is whether it's a stock engine or a built one, we are dealing with parts that have limitations. In that kind of high boost "on a built motor" you are dealing with the same principals. 17psi on a motor that has a 10.5:1 cr is bloody nuts...lol At 17 it was running a 22.5CR, dropping to 14 is bringing it to 20 or so. Its not about boost numbers, cant think that way. CR is the answer in my opinion. Man I could be so off on this but this is my theory and has kept me safe so far