ORIGINAL: britbrat
I don't recall seeing what aircraft the "screaming TT" is in. If it is in a slow airframe, an 11-4 will not under-prop it. I use 11-4s on float planes with TT.46 Pros & they tach @~ 13,800 rpm static with the 11-4. This is just fine for the application, but it would be under-propped on an Ultra Sport 40, or something similar.
What are you flying?
Seagull PC9