TACX Cycleforce Excel


I searched the threads for some answers but I guess I might be the only person using such a dinosaur of a trainer!

TACX Cycleforce Excel with the programmable LCD display, I use ant? garmin sensor to run Z-power and have tried to dial in the resistance level on the TACX Excel to match the wattage shown in z-power.
My FTP is 266 and so I set it up so that when I am at threshold heart rate and z-power shows 270w in the zwift screen I also see 270w on the Tacx Excel display, so far so good and it appears to be an honest level…with representative w/kg and speed on flat terrain… I have selected unlisted trainer in the set up.

The trainer doesn’t have a stepped resistance adjustment that I can find, like 1-10, I can either set the maximum wattage that I want to hit, or set the wattage display to 0 and set it to slope +1.

No matter how I try to set up the resistance it is either too high (Tacx 150w = zwift 50w) or too high (Tacx 300w = Zwift 400w) so when I really go for it… my zwift numbers are too high…

Is anybody else using a TACX Excel and how do you set yours up… wattage or slope or a combination of both…?

Can I ask how you know your FTP is 266?

I have done an FTP test at the gym on a wattbike where I am an instructor for Sufferfest. (Actually done 5 tests this past year and am gradually creeping up…)
My first FTP/VO2max and LTHR test was done a year ago at a sports science lab, 220w@155BPM, the 2nd, 3rd, 4th and 5th tests were done on a wattbike at the gym, most recent was a month ago 266w@161BPM.
Obviously I get a better ride experience on the wattbikes, but sometimes I prefer to ride at home in my paincave on the trainer… can’t justify getting a compatible trainer when old faithful still does the job.
Beginning to think I might have to run the Tacx Excel on program 0 and then manually adjust the resistance wattage to a level I am happy with… it’s a static resistance thing, so if I set it to 270w then it will always hold 270w of resistance regardless of cadence, for sprints and hills I have to ramp the resistance up to 400w+ 
If I set the base setting to 400w I can change gears to make it easier… but the speed on zwift drops right off…

Smart Trainers are getting more & more reasonable. Just might be about time for an upgrade. A refurbished Kickr2 is 999 & that will get to the premium Zwift experience.