td05 spool around 4-5k n td04 spool around 3k.
bigger turbo tend to save fuel when cruising around 110-140 because it not spooling.if cc nt big enauf it will lag.the flow not strong enauf to push the turbine.housing inlet to big.
smaller turbo already start spooling around 110.fc like crazy.town drive should be nice but nt good for hway.housing inlet smaller.
so choose your turbo wisely.
btw campro bot...u kinda crazy.even u got strong internal ur block can sustain in long run?

turbo spools all the time. On wide open throttle from start, TD05 will build pressure around 5k above. TD04 2-3k above but puff out of breath around 5k. That's where your boost will drop slightly or equalize with atmospheric pressure.

Big or small turbo has minimal to do with FC. Tuning, way of driving and setup yes. If you use big turbo, but never build up pressure, your engine will consume petrol like average NA. If you boost, depends on the tuning, stoichiometry, efficiency of the power transferred and Power to weight ratio is perfect, your FC will be good also. You can hit 5k rpm with vacuum. Controlled entirely by your foot. There are alot of ways to reduce lag slightly. A bit too lazy to elaborate.

Your turbo will spool to build up pressure when its either wide open throttle or throttle opening is big enough to flow into the intake manifold. don't get confused. Pressure in the intake manifold may not be the same as your intake piping. All is regulated by, your BOV, your Throttle body and your wastegate.

Yes. Running up to 1 bar with stock internal for S4PH. No problem. Only problem is traffic jam and you cannot use all the pawa. Monitoring is essential if your setup is half complete. A complete setup will have proper ventilation ensuring the engine bay does overheat, a good management, injectors, fuel pump ensures adequate supply of fuel and injection volume, Good & correct tuning with proper ignition timing, and good boost regulater. E.g boost controller or wastegates.