hey i have some questions about turbocharging the m42
here in denmark we have so complex engine performance rules and its almost impossible to turbocharge and supercharge your car because we have a rule that says you not can exceed 20% of the original horsepower but some older cars can avoid the rule like my 318is because of the age of the car and its bigger brothers

but my car according to our traffic Agency my car got the same brakes and suspension as a 325i that has about 171 hp and add the 20% to that is 205hp but dose the 320is have the same suspension and brakes to?
our rule says that a turbocharger always makes over 20% of the cars original hp. but in my case im tuning over the 20% barrier and that "unlocks" the turbo charger.
so my real question is, and how much hp can the crankshaft take and other internal and driveline parts take. i know that i have the get new pistons and etc.
my goal is about 205-240 hp on really low boost and as much as possible on moderate/high boost, and i have a thought to some times run on e85
the car is at the moment my daily drive and trackday car that ive just refurbished exept the engine. but it have to be reliable but im going to get an second car as a daily driver later this year but still.
hope you guys can guide me to the goal and a final decision
jonas