first things first.
why are you mixing engine oil with fuel? - who told you to do that and what are you trying to achieve from this?
The blowby pipe is supposed to be connected to the turbo inlet as it applies a negative pressure to the crankcase and keeps it vented and prevents blowing oil seals. If a lot of oil is shooting out, then open up the valve cover and clean the baffle plates in it, they are probably clogged. Do not leave that pipe open to air unless you like to rebuild your engine every couple of years.
what engine sound is too loud? - is the fan permanently stuck on?
and how did you get the turbo repaired? - did you install a new cartridge kit? or some lathe guy cut some bushings for you?