You can go over 3K. I'm IS38 5150 also. As long as you dont spike & hold full boost above 3'rd you are good. Since I'm assuming we are on the same base map.
I wish I could. I have data logs corroborating the fact I’m experiencing clutch slip below 3k. It’s exacerbated even more going up to redline, obviously.
Granted there will be random times when I shift ~3k or a little more and it’s fine. Most times, there’s slip.
Peak torque is 2700'ish on the IS20. You'd have to keep it under 2500 or over 4400 to stay out of the torque bulge. I hope you like downshifting a lot.
I’m IS38. See post above about my data logs corroborating the clutch slip.
Obviously I don’t enjoy not getting to drive my car the way I want to and should be able to; hence my eagerness for COBB to release this TCU tune.
Thankfully the majority of my driving is highway, so it’s not terrible to stay in my target RPM zone. Also, as mentioned by another, engine load plays a big part of it in addition to rpm. It’s a balance.