Holy Cow. 348fwkw! You have to be kidding. That is some pulsar mate. Congrats. I bet a lot of time and effort has gone into that.
I don't know why someone would make a dyno and calibrate it extremely differently just because it connects to your car in a different way. I can guarantee from the feel of the car compared to how it was with the old T25, that it is making a considerable chunk more top end power than it used to. And not just from the extra surge or rush making it feel like more. I am going to get this 2" exhaust tip replaced with a 2.5" and put it back on a dyno dynamics in this colder air to get a comparison readout. I am pretty confident it will read more on Jake's dyno that originally measured the old T25 setup at 137fwkw.
Re: drivability. Mate, the old T25 setup was certainly more drivable in terms of things like, exiting a roundabout in 2nd gear, the boost would more easily slap up to 15psi quite quickly and away you'd go. The boost threshold (what many people incorrectly call "lag") is definately higher (laggier) on this turbo. But its kind of like not that much worse compared to how much extra top end gain and durability this turbo gives it. Also pumping out colder air from not working as hard means safer power and more power earlier from colder air.
If you look at that boost vs rpm graph carefully, you will see that by 4000rpm, its already making 7.5psi. That is very similar psi that a lot of the other mild k11 turbos are running and making at the same rpm. So you could say it still feels fast at that RPM compared to a stock micra. There is certainly some decent torque surging feeling at that RPM. Its pulling harder than a normal micra and starting to pull away and feel some nice grunt.
In that next 1000rpm (providing you keep your foot to the floor), the power goes crazy. It more than doubles by 5000rpm. It goes from 50fwkw at 4000rpm to 111fwkw at 5000rpm. So as you could imagine, that 1000rpm is where its all happening. That is the spot where the wheels will start to spin and the afterburner comes on. In that sense, this part of the rev range feels like a typical old fashion non-linear turbo power band. Like whoooooooosh!!!
But remember, dyno graphs are always taken with the foot to the floor. As the car has already made 7.5psi at 4000rpm, I can give say only half throttle or 3/4 throttle to maintain that kind of boost or even a fraction more, say 10psi and the car still feels fast and strong, without the huge whoosh at the end. That would then feel similar to some of the more milder turbo'd k11s. The big power jump with the foot floored between 4000-5000rpm really is a bonus on top of already decent every-day boost and power levels.
If I leave it in the "low boost" setting, I can't find the graph right now, but I think it makes about 11psi or something like that. That doesn't come with the huge whoosh at the end, but you still get fairly level response. Look, below 4000rpm, there isn't a helluva lot happening. On the old T25 setup, I would say that same point would feel like about 3000-3500rpm. So its a bit "laggier" but really only talking about 500rpm I think for some really good advantages.
Considering that the action starts above 4000rpm, and the car revs all the way to almost 8000rpm, you are easily always in the power band after a gear change, so if you are really getting up it and going through the gears, you are always in the crazy power band area. So it can go really fast. That's why the quarter mile times would have improved a fair bit from before. With the old T25, after about 6000rpm or something, the car started to feel very linear again, like torque was dropping off and power was only gaining simply from the rpm increasing, not from any increases in torque.
I would prefer the current setup. To sum it up, it has pretty decent everyday response, but the stupendous afterburner is there for kicks when you need it