CANbus system in 2021 Toyota killing my Flow

[Anubis1631]

Hey y'all I want to preface this by saying a big thank you upfront for anyone who can help me. I own a 2021 Corolla Nightshade Edition and I am upgrading my sound system I have the stock HU and have came across a few specific issues about the newer than 2019 Toyota vehicles electrical system that I am afraid are going to put a halt to my project.

 

Details - HU: Stock, Amp: 2000 RMS, Subs: 2 12" Digital Design 600 Redline, Alternator: 140 Amp Stock, Battery: Stock Toyota BCI Group 47

1. From what I was reading they are using a CANbus system now and you have to be extremely careful if you want to put a high output alternator on the vehicle because it can change the shift points on the CVT transmission. I did contact the big alternator makers and only one said that they do make one for this motor and vehicle. I didn't get an explanation from Mechman, Ohio Gen or any of the others that I spoke with about why they don't make them just that because of the CANbus system they don't make them past model year '19. Apex High Output Alternators swears they make one and I ordered it (probably a bad idea) but there's a 100% money back guarantee I'm just hoping that it doesn't effect the shift points. I posted on the ToyotaNation.com forum and they made sure to tell me that there is a 140A Main Fuse for the Alt. and that's another issue I have to figure out as well by adding another fuse inline I believe.

2. There is multiple ways through batteries to power what I need as long as I can recharge them as fast as I need to. So I was going to go with a battery dummy with just the posts up front and buy an XS Power Titan-8 to put in the back to power the full car and system but I'm not a professional and am looking for solutions to the issues of A- The alternator does work and all I need is to get a better battery (any suggestions would be appreciated) or B- The alternator doesn't work and I have to use the stock alt and figure out a workaround to feed the amp the juice it is craving as fast as possible.

 

There are so many different opinions and everyone has their own way of doing things so any time I try to find answers it's like information OVERLOAD and I wind up more confused than I started

Any help is gratefully appreciated, thank you so much!