Lexus Tuning Help

I have been looking trying to find information on tuning Lexus vehicles and haven't had any luck. I have a IS300 personally, but just had a customer come in with a 2015 Procharged RC350 that is having multiple O2 codes. I am trying to find out if there is a way to correct them via tuning, or if there is software available for it. It is my understanding that cars ECU is all stock, but I have reached out to the company that built the car to find out more information. I am really just curious as to if there is any software available yet to re-flash Lexus vehicles.

I would contact a vendor that deals with GS350 and IS350. Just Googling around I see this for a GS350. https://www.rr-racing.com/RR-Racing-Lexus-GS350-ECU-Upgrade-Tune-p/gs350tne01.htm

That is cool but i want the software and hardware to be able to tune it myself not rely on another company to do it for me. The IS i have is a 2001 IS300 so a totally different car.

these niche platforms often have 1 or 2 companies who dominate the market. They put the investment in to access the ECU and figure out how to tune it. So they make their money by selling canned tunes or eTunes, or by selling expensive shop licenses to use their software.