I’d set FTP 314 and do a sweet spot workout to verify. Your low score on ramp test relative to 8-minute test says you would benefit from doing more VO2 work. For the vo2 work we know from TR blog and podcast the % intensity has to be determined thru trial and error. And the fact that vo2 work is highly personal is reinforced in workout notes, here are the notes for Mills workout:
And my transcription of what Coach Chad said in the part 2 vo2max deep-dive (episode 191)
- VO2 work is really subjective, this is why 2-3 min interval workouts at 120% don’t work for everyone, and we say it may not work for you and some people can work above 120%, some people below 120%